For the sake of transparency, if anyone is curious about that tweet saying "yaoi was a genre created as a stimulus after ww2 by straight women for women" (paraphrased), the source they got it from is not actually saying that.

It was a mix of actual lying, misinterpretation and gross paraphrasing. The source was simply informing on the origins of BL as a genre in the manga world and makes no claims about WW2, or straight women.

To paraphrase a complicated subject: it appears it was kick started by women wanting to represent the gay rights movement among other things, and was published in shoujo magazines in "shoujo art style", hence the misconception of "written by straight women for women"

which arguably, the target audience was majorly women considering the audience of the magazine. However, there is no evidence to suggest it was exclusively written by straight women and with only women in mind. A genre target audience is not the only people that read said genre.

(ie, I read shounen yet i am not a young man, romance stories may often be written from the perspective of a women by a woman but that does not mean male authors and readers do not exist, if you catch my drift).

In regards to the WW2 part, even the source has no idea where that came from haha
But also, if you see the OG tweet, they may be dumb but don't harrass them, they're like 16. Not that you should dogpile anyone, but I thought i'd mention to be sure.

Sources if anyone is interested (they're not perfect, but reading all of them together I would say helps inform your perspective on the bigger picture overall)
https://yattatachi.com/history-of-boys-love
https://www.japanpowered.com/anime-articles/a-brief-history-of-yaoi https://rottenboysclub.tumblr.com/post/178036881344/could-you-tell-us-more-about-year-24-and

https://twitter.com/Bagel0001/status/1264520513793081344?s=19