I can attest, autism runs on my mother’s side of the family. I have two uncles who are low functioning.

One’s practically a child mentally with an obsessive recall for music charts over the years, and absolute statistical knowledge of the NY Giants history. He’s brilliant, with essentially encyclopedic knowledge within his extremely narrow interests, but can barely take care of himself otherwise. The other is a somewhat independent and capable of dealing with life, but… just inept and weird, and not smart at all.

I’m also mildly autistic (Asperger’s, on the old system I guess) and smart. Not a genius, but fine. It’s been pretty easy for me to pick up on complex concepts and tasks in life, so long as it’s not too math heavy. I’m working in IT automation/cloud/etc. and generally doing well in life. A little socially awkward and introverted, but happily married and successful overall, more so than average in my age/peer group.

although most issues with autism is dealing with neurotypicals.

We went down the slope once people started using it as the next euphemism for "retarded".

At the same time, to my knowledge autism (and ADHD for that matter) aren't well enough understood that we can say for certain "all these things we consider autism are caused by the same thing", it feels more like a grouping of symptoms and as usual you get the diagnosis it if it significantly interferes with your daily functioning.

I can tell you that it very much did (and still sometimes does, though it really helps that most of my peers now think similarly) interferes with my life that people seemingly expect me to know magic to understand what they mean, and inversely their magic that works on everyone else malfunctions on me and gives them completely wrong ideas.

But I am also entirely capable of living life on my own, and fundamentally it does make sense that there needs to be some distinction between someone that needs constant assistance vs someone that is mostly fine if people show some basic attention to not sensorily overload them/can mitigate the issues largely on their own as long as no one prohibits it.

The thing is, it is very much a spectrum and outside of the clear "incapable of surviving on their own in society" and "does fine but people think they're weird" there's a ton of "does generally fine but if multiple people start talking at them at once they might shutdown", "is caused distress by a few basic tasks but can deal with it, it's just a stress factor" and "needs some active assistance, but is mostly independent" and people (rightfully so) neither want to be told "well your problems aren't real because you seem fine from the outside" nor "you're too disabled to live a normal life" when it isn't abundantly clear that that's the case. And trying to distinguish between the extremes will necessarily lead to that for a lot of people.