I watched a few Naruto videos on youtube recently and something I've noticed by reading the comments is that one thing that Naruto fans agree on is that Kishimoto is trash at writing female characters compared to the male characters. It made me think how in some shonen, all the thoughts and effort are expended on the male characters and (indirectly) their relationships with other male characters, while the female characters are treated as expendable and it reminded me of common tropes in bl. The only difference is how the female characters are treated and who is writing them. Female characters in Shonen - eye candy/sexual object, has no autonomy other than being the male lead's Love Interest. Female characters in BL - the fujo (cringes) friend, only exists to get in the way of the m/m couple. You know that handshake meme? Imagine that but on the left side it says "BL authors" and on the right side it side "Shonen mangakas" then in the middle where the hands join, it says "writing male characters and male relationships that are fleshed out while the female characters leave a lot to be desired." Thank you for coming to my TED talk.
Yes, good thing kishimoto don't know, don't care about the toxic foreigner's opinion or else it would affect his work
Both are fiction aimed at particular demographics- young boys and women- which, while not necessarily justifying 'poor' representation of certain groups, at least makes the reasons understood. I'll take your word about female representation in shonen provided you are a woman. But as concerns BL, I do believe it needs more of a male perspective for balance, as a genre depicting males but targeted at, read and authored by females doesn't exactly inspire confidence in any judgement made on it as regards portrayal of males and their relationships.
Actually it's most probably for the attention of the group of 'certain' audience ( just my opinion tho )