"In this case, regarding autism, it's called "spectrum" for a reason"

Yes, it may be easy on HN to forget because we get a lot of "high functioning autists" here, but the word "autism" encomposses the 15-year old boy I met stuck in a wheelchair, whose only verbal communication is what I can only describe as a "bark" when something was not to his liking.

"Mental illnesses" do not top out at "a bit quirky". It is neither inaccurate nor insensitive to observe that some people are simply incapable of functioning in the real world. In fact holding the belief that there is no such thing can itself harm people by preventing them from getting the highly-invasive help they need.

That said, if we're talking about people who are in the workplace at all, we're not really talking about that set of people.

I read the quoted statement in the context of the rest of your comment, which pertains to a workplace environment where the subject already lives and works in the real world, so they'd be on the higher-functioning end of that spectrum. There are certainly people who don't fall into that end, though.