These types come up a lot when dealing with BPD, too. They're narcissists, plain and simple. Think about it:
-They feel they "deserve", or have a right to be surrounded by a certain "class" of people (usually one they've judged out in their own minds), and not "bothered" by any "others".
-They take mental illness personally. Meaning they see someone with ASD (or whatever weakness they decide to pick on), and their brain immediately goes "Ugh! This is a slight against ME! I am too important for this!".
-They claim to "know" unknowable things (how someone is thinking/feeling in their head, etc), because they're super smart and also very special!
Basically, if you find a narcississm checklist, these people tick every box. They view ASD the way they do because their brains tell them this whole world was made for them (creators of the site) and them alone.
They're the same people who will try to be "edgy" by suggesting people with severe disabilities (e.g-Down Syndrome, cerebral palsey, spina bifidia, etc) should be euthanised at birth. Yes, I've unfortunately met these people.
It honestly comes down to the fact these people see a problem, or see people with a problem, and instead of learning more and trying to fix things that way; they are lazy, and would rather sit around and say "eh, just get rid of 'em all!"
Most people do not feel this way, but its the loudest and most ridiculous group that gets attention.