Request uncommon sense

Correct~! Novels focused on world building should explain this, but generic isekai novels authors usually focus more on the protagonists

As for the knights... this is not "that one country where humans grow on trees". Training a knight takes years. They are official part of the kingdom. Adventurers are the unofficial group that is basically "legal mercenaries"

Taxes are either spent wastefully by corrupted nobles and riches, or spent to nurture the kingdom. One way of doing so is by raising the knights. Other ways... i dunno

if light armor is made of stacked leathers (which is pretty good / NOT bad), then high end armor might be plate armor or gambeson

 

yep yep! such a convenient thing to have~

 

Quality of materials, quality of manufacture, how well it is fit to the wearer, etc. There are many factors that affect the quality of armor, and the wealthy tended to be in more expensive and better made suits that were much safer. There was very little that could penetrate high end plate at the end of the medieval period, but low end plate, or even lesser armors could be penetrated much easier. Heck i was only with the advent of modern gunpowder that it it fell out of use, even black powder weapons had trouble penetrating well made plate armor (they would test armor by shooting it, the mark it left showing the armor could withstand a bullet is where the term bulletproof comes from)



There was a constant arms race in history between weapons and armor, and at every point there was always cheap sets and better quality expensive sets that offered better protection, even in plate armor there was mass produced suits for militia's and soldiers as well as high end custom fitted sets used by the rich and nobles that protected better due to having better materials, workmanship and the better fit meaning that there were smaller gps which was the weakest parts of the armor sets.

Gambeson would be low tier armor, on the same tier as leather only much cheaper and easier to repair so it was much more common (leather armor was rare for several reasons) Though it would be a component of most superior sets because no one is putting metal against their skin.

Leather is actually something that does not make much sense, unless there is some factor making the parts thick enough to be of use more common. Gambeson was just so much more cost effective.

In some series (death mage being a good example) there are areas that are (mostly) reclaimed with little to no monsters, or only weak ones. and those are where most of the farming takes place, with monsters on the frontier areas that are still wild and dangerous as well as potentially contaminated in some way. The question is if the tamed land is static, expanding, or disappearing (like in Goblin Slayer). The problem is we only see the areas the characters visit, so i can be hard to tell how much of the world is safe vs a death trap

 

(Sorry that I'm not going to respond to what you wrote right now, short on time)
The reason I asked if you meant plate armor because there was something interesting about arrows vs armor that I came across awhile ago that I thought you might be interested in reading.
I'll leave a chunk of it here in a spoiler.

Spoiler

"Discussion and Summary
The relative absence of armor in the Southeast at the time of contact is
puzzling. De Soto’s chroniclers made no mention of it, nor did the accounts
of later Spanish explorations led by Pardo and de Luna. The preceding
information on armor from various cultural areas of North America
suggests it should have been present, since elaborate armoring seems
to correlate with population density and the necessity to control access to
essential resources such as farmland, fishing sites, or trade routes—all factors
relevant to quality of life in the Southeast.
A common explanation for its absence stresses the supposed inability
of the armored warrior to dodge projectiles or fight with shock-weapons—
an observation based on a Western preconception that equates armor
with the heavy metal plate worn by the classic European knights. However,
a more apt comparison lies in another warrior tradition, one that
used leather and wooden armor—the Japanese. Modern-day kendo, the
“Way of the Sword,” offers valuable insights. A kendo fighter wears a
thickly padded jacket and light canvas pants, the dogi, and on the upper
body, a cuirass, or do, today made of thick plastic. (In earlier times heavy
lacquered rawhide was shaped over a bamboo interior structure.) Around
THE STRONGBOWS
139
the waist is an apron, tare, which protects the stomach and hips. Over the
dogi a multipleated culotte reaches from waist to ankle. Completing the
outfit are gauntlets, or kote, and a cumbersome helmet, men. Even though
the kendo player is more impeded than an Indian warrior wearing a rodarmor
cuirass, or war shirt, well-trained kendo competitors can move so
quickly that the amateur observer is unable to see their lightning-fast
strikes and feints. The speed of the kendo fighter strongly throws doubt on
the argument that armor was abandoned because it slowed the Indian
fighter.
Sparse archaeological evidence and accounts by a few Spanish explorers
confirm the presence of armor up until just before contact, and all Southeastern
experts assumed, even in the absence of proof, that wood and hide
armor was used in the Southeast in early times. How could it be otherwise?
How could Indians all over North America have used armor but not the
very advanced cultures of the Southeast? The question then becomes,
what factors led to armor’s virtual abandonment by the very militaristic
Indians of the Southeast, assuming that like all other North American
groups, they had it at one time?
One strong consideration echoes that which led to the abandonment
of armor in Europe. The key factor, of course, was the introduction of a
weapon, the repeating rifle, that could easily and repeatedly pierce armor.
The rifled barrel enabled guns to shoot farther, straighter, and with more
velocity, and mechanisms that allowed repeat shooting positioned the
fighter with such a weapon as to be worth several of his predecessors with
muzzle-loading long guns. The armored knight finally reached the point
where adding thickness to the plate to defeat the new rifles was counterproductive.
He became barely able to move under the weight of his armor,
even though for a time it could stop a rifle bullet. But this historical account
also applies to the Indian archers of the Southwest, who at the time
of contact could fairly closely replicate with their bows and arrows the effects
of the repeating rifle.
Anecdotal evidence of the force with which a Southeastern warrior
could deliver an arrow is found throughout the chronicles of De Soto’s
travels in the Southeast. And even though the Spaniards in the sixteenth
and seventeenth centuries also experienced hostile Indians in the Southwest,
Southern Plains, California, and Northwest Coast areas and offered
passing comments on their bows and arrows, the entirety of their descriptions
is perhaps a third of that written about the bow and arrow among
the Southeast Indians.
NATIVE NORTH AMERICAN ARMOR, SHIELDS, AND FORTIFICATIONS
140
The Gentleman of Elvas, one of the chroniclers of the De Soto expedition,
wrote:
Where the arrow meets with no armor, it pierces as deeply as the shaft from
a cross-bow. There bows are very perfect; the arrows are made of certain
canes, like reeds, very heavy, and so stiff that one of them, when sharpened,
will pass through a target. Some are pointed with the bone of a fish, sharp
and like a chisel; others with some stone, like the point of diamond: of such,
the great number, where they strike upon armor, break at the place where
the parts are put together; those of cane split, and will enter a shirt of mail,
doing more injury than when armed. (In Jones 1999, 18)
The bows of the Indians of Louisiana had a pull weight of 40 to 50
pounds (Kniffen, Gregory, and Stokes 1987, 144), and a 50-pound pull was
observed in many parts of the Southeast. The penetrating power of the
Southeastern bow and arrow is underscored by an account of an arrow
armed with a fire-hardened whittled tip that penetrated the armored leg
of a Spaniard and entered the body of his horse. Hardy, in his work on the
longbow, wrote:
But extraordinary penetration has been claimed for some Indian weapons,
and sworn to by eye witnesses. During the Florida campaigns, the Spaniards
again and again found their breastplates, which would stop musket
balls, penetrated by arrows from the bows of Creek Indians, Choctaws and
Chickasaws. An Indian captive, made to demonstrate their shooting methods,
shot clean through a heavy coat of mail, the arrow dropping to the
ground beyond the back of the armor. He also completely penetrated two
such mail armors, one hung on top of the other. (1976, 168)
According to Spanish accounts, some Southeastern bows were as thick
as a man’s arm, often over 6 feet long, and accurate to 200 yards. In an
early engagement, ten of De Soto’s Spaniards were killed by Indians while
foraging, even though most were wearing good armor; the soldiers’ bodies
were “pierced all the way through” (Steele 1994, 13). In another account,
a horse was killed when an Indian arrow passed through its cloth,
saddletree, and pack saddle and carried such force that more than a third
of it penetrated the rib cage (Hudson 1997, 66).
In an early account from English settlers in Virginia, the power of the
bows and arrows of the Indians was tested.
One of our gentlemen having a target which he trusted in, thinking it would
bear out a slight shot, he set it up against a tree, willing one of the savages
THE STRONGBOWS
141
to shoot; who took from his back an arrow of an elle long, drew it strongly
in his bow, shoots the target a foot through, or better; which was strange,
being that a pistoll could not pierce it. (Swanton 1946, 581)
Many testimonials from the Spanish, as well as the early French and English,
in the Southeast could be added to the above. One fact is abundantly
clear: The arrows of the Southeastern Indians, like the bullets from
a rifle, could pierce metal armor. In addition, the manner in which the arrows
were armed, or tipped, is crucial in understanding their effectiveness.
In his article “Antler-Pointed Arrows of the Southeastern Indians,”
Charles C. Willoughby made an astonishing statement. “In studying the
arrows of historic primitive peoples of different parts of the world, we find
that, excepting among the Indians of central and western North America
and in a few other restricted localities, flint points seem to have been the
exception” (Willoughby 1901, 431). Additionally, little evidence exists of
stone arrow points in New England in historic times. The key is that only
certain types of stone can be chipped effectively, and they are not evenly
dispersed across North America; however, other suitable arrow-tipping
materials are. The major big-game animal hunted by Indians everywhere
in North America was, with few exceptions, the deer; and “buckhorn,”
or deer antler, was widely employed in tipping arrows. British trader John
Adair wrote that the Cherokee used arrows pointed with “scooped points
of buckhorn,” and De Soto’s chroniclers observed arrows in the province
of Cofitachequi that were tipped with buckhorn “wrought with four corners
like a diamond.” Archaeological evidence of antler arrows is found
throughout the Algonquin area along the Eastern seaboard and from
Maine to as far west as Arkansas (Willoughby 1901, 434).
A study by Nathan Lowrey, “An Ethnoarchaeological Inquiry into the
Interactive Relationship between Northwest Coast Projectile Point and
Armor Variants” (1994), lends insight into the implications of antlertipped
arrows in the Southeast. Lowrey replicated Northwest Coast Indian
suits of wooden armor, as well as bows and arrows with stone, slate, and
bone points, and learned that the stone- and slate-tipped arrows shattered
against the wooden armor, or merely stuck into it. The bone points, however,
punched through it.
Significantly, Ames and Maschner observed:
Stone projectile forms and styles are quite variable on the Northwest Coast
while bone projectiles are similar across broad regions. These bone points
are relatively long and slender, with a wedge-shaped base, and have been
NATIVE NORTH AMERICAN ARMOR, SHIELDS, AND FORTIFICATIONS
142
found outside the palisades of defensive fortifications. While having a long
history on the Northwest Coast, a proliferation in numbers may correlate
with the arrival of the bow and arrow in the region. (1999, 213)
The ability of the repeating rifle to fire consecutive shots with enough
force to pierce metal armor ended the military use of plate armor in the
West. The archers of the Southeast replicated the effects of the repeating
rifle. With their bows and arrows, the Southeastern Indians were ahead
of the evolution of the repeating rifle in the West. Under these circumstances
there is little wonder that the Southeast lacked armor at the time
of contact."

source:
"Native North American Armor, Shields, and Fortifications" by David E. Jones

 

I might be missing something here, but the only time they explicitly say what type of armor was used there is against mail, which mild steel arrows could penetrate. Otherwise thanks to missing information (and that historical sources are very often inaccurate, lies or leave out important details) there are to many questions in the story. Thin plate could be penetrated more easily then thick plate, but the quality and strength of the materials materd allot. for example antler is supposed to be harder then mild steel, but not as hard as hardened steel.

Though I just do not trust any record without testing to show what was going on. I could easily see people going against "ignorant savages" to buy cheaper armor thinking they did not need the extra expense, or thinner armor/padding that would cause less overheating, etc.

But ya, if someone develops a weapon that their armors can not adapt to, they will drop the armor since is encumbering over time (and has other issues like heat regulation)