I wonder if these people are really autistic, though, even if some team of shrinks has diagnosed them as such.

There is certainly a category of people (mainly men) who are intelligent and eccentric, but socially inept and/or disinterested in the 'normie' world, they're obsessed with certain topics or hobbies (data, dissident politics, animals, trains, whatever) that other people don't get, but they don't have the problems that is traditionally associated with autism.

This is anecdotal, but most of the people I've known who were diagnosed with autism are below average intellectually and they have a lot of problems with things like basic hygiene, tying their shoelaces, making their beds, not being able to handle crowds or loud noises at all (which is not the same thing as simply not liking parties), lashing out, etc. I'm not talking the severe cases either. If you've ever watched the Vietnam War film Full Metal Jacket, Private Pyle is what those autistic people are like.

As for ADHD, I've noticed that's a condition that seems to always magically disappear when they reach adulthood.