Do you guys think there is a demand in grape in Yaoi and BL and that's why most of them ha...

Ironically, it also has a bit to do with purity culture. The bottom saying no and they don't want it make them seem "pure" and more "attractive"

not exactly but there could be. i think a lot of authors incorporate r*pe into their yaois in order to grab the reader's attention as soon as possible without caring for it leaving a bad taste in some people's mouths. some authors use this element skillfully but i think a lot are unable to and use it sloppily,, rape is very different from sex but both kinda come off as erotic (even tho rape ofc isnt) nothing grabs a reader's attention better than intimacy between characters (whether or not its mutually consenting)

Uhhh Idk if there’s “demand” for it. Like,, are ppl really demanding r@pe???????????? Thats disgusting to even type. Imo I think toxic BL has become such a common trope bc readers love it & r@pe just comes with that, it’s like a package deal

Ironically, that mindset stems from men. And most bl artists are women, catering to women and gays.

aside from whoever is asking for more of it(idk, maybe some people are) I think it goes without pushback from most readers (particularly in their countries of origin) and it's a convenient plot-streamlining device for authors since it establishes character dynamics and tension between characters, forces sex scenes without much setup, gives immediate sympathy points for the victim, and creates ongoing conflict for the story and relationship. when you're working on deadlines and tight page/panel counts, shortcuts like that are godsends.
people are consistently fascinated by taboo and toxic relationships, so I'm not sure it's something that ever really dies down in popularity.
it's most irritating to me when it's in series that aren't actually the toxic abuse-fests that seem to be having a popularity/publishing surge. that implies the creator just has a poor understanding of mutual sexual interest and consent.