

Not Lemmy specific. There was US legislation related to the word being deemed offensive fifteen years ago (given the slow nature of Congress, it wasn’t a new sentiment then, either): https://en.m.wikipedia.org/wiki/Rosa’s_Law
Fair enough that plenty of insulting words could be cast as abelist: but my guess is that a word like “idiot” is old enough that most folks called that in a medical context aren’t around any more. Maybe I’m wrong though: plenty of folks do push against saying things like “crazy” in an insulting manner.
Yes, most Democrats aren’t Left enough. Some are trying to push the party to the Left, however.
I think the confusion here is your blanket “they” is conflating the mainstream Democratic party instead of those of us who are pushing this stuff at the grassroots level, e.g. actual progressives/Leftists etc.