Given how they are a cluster of conditions where most people have some subset of noticable conditions, I'm not sure there is a clear way to differentiate them.

Also, the last person I saw who brought up this argument about how functional they are and how it was unfair to people who are less functional was in the same comment also simultaneously talking about how they're depressed or suicidal from extreme loneliness and strongly wished to be cured of their autism. That hardly seemed functional to me if you are struggling so much with life even if you can pretend to be functional enough to hold some jobs. I think many people have a strong tendency to downplay their own suffering. You can see the same behavior from people who've been victims of abuse who frequently will deny they've ever been abused, but if you ask them to describe what happened, they'll describe abuse and then just try to say it really wasn't that bad or that such is normal.

Also, we already have terminology to refer to lots of those traits commonly associated with autism. Nonverbal, hypersensitive, speech-processing disorder, and more. If there's a reason to communicate those things, you can do so with or without mentioning autism.

If helping someone with mild symptoms took away from those with more severe symptoms, I'd see a point. But I haven't come across any evidence of that.

It's important to remember that there is more going on than what we see. I can get by well enough for most daily living tasks, but when I'm at my limit I'm treated like I should be able to handle it like a neurotypical. I hate having to explain to my managers at work what it's like to shut down from overstimulation. I hate having to be seen as "unreceptive" to changes just because it takes time and understanding for me to adjust to new routines.

I'm trying my best, but to separate "mild" autism from "severe" autism diminishes the struggles that many of us go through, especially for those of us who didn't receive diagnosis or treatment as children. I've had to learn how to navigate this bizarre world on my own, but just because I can "pass" sometimes doesn't mean I've mastered it.

I see this sentiment even in my own coworkers, which is sad because we all work with autistic children. I have a learner who's exceptionally bright. He asks questions that could only be properly answered by a college professor. Sometimes when discussing him, my coworkers will ask, "Why is he even here?" I have to explain that just because someone's intelligent in some ways, that doesn't mean they're caught up with social and emotional intelligence. The kid has difficulty regulating himself, while he's made massive progress in social skills while at our school - I've seen him grow from a kid who only wants to play alone and who would get annoyed when others tried to play with him, to one that happily joins in on games with others and even tolerates when another kid has a drastically different play style.

He'll be getting ready to graduate and go off to public school soon, which will be bittersweet for me. I was a lot like him as a kid, and I can already imagine some of the difficulties he'll face - many of which will come from adults who see his intelligence and assume he can do more than he's capable of. So when I work with him, I make it a point to tell him that not everyone will understand what he's going through, while teaching him functional communication to get his needs met regardless. I'm sure this little bird will fly high some day, we don't have to teach him how to soar. But before he can get there, he has to learn how to land himself safely - that's where I (and the rest of his teachers) come in.