saying "people who ship this / like this character are straight / cis" even when they know damn well that's not true

I've seen this around a ton too, and it's literally just to establish who the 'acceptable' targets are. The most recent thing is targeted rejection and mockery of "fujoshis", which are always categorized as exclusively straight women who treat male/male relationships as a fetish, but indiscriminately sweep up swaths of queer and nonbinary people in the process.