Idk, I've had three clients diagnosed with schizophrenia and, while one was fairly racist, the other 2 were rad as hell, and I don't think the bigotry had anything to do with the racist one's mental health- just culture.

In fact, I think bigotry is a pretty normal human thing to experience. Psychotic symptoms (and poor mental health in general) can certainly lead to and exacerbate bigotry, but I don't think pathologizing bigotry itself makes much sense. I mean yeah if someone is experiencing bigoted delusions/obsessions/compulsions/etc then we should call that what it is, but bigotry itself is typically better explained by culture and natural human behavior

Edit: but I do like the idea of coopting it. I think it would be hilarious to respond to someone using it as a dog whistle with something like "haha I'm [autistic/ADHD/BP/etc] too." I think that would really rustle their jimmies