The few times I’ve been hit with this in conversation I don’t even trip. Like sure even from their premise of “mentally ill” how is it ok to regulate their lives/deny them medical privacy, discriminate against them, be generally hateful or shitty towards them? Like being abelist isn’t any better than being a transphobe, it’s not an excuse even if they do personally think it’s a “mental illness” like either way you’re showing how shitty of a person you are