It's not from one extreme to the other. There are those of us in our 40s who were non verbal as kids and have since become semi verbal/selective mutism (Some are completely verbal too). We struggle with verbal speech, self care, hygiene, food, etc but can use the bathroom and toilet independently.
Some of us are awfully isolated due to constant overstimulation and dysregulation when in regular contact with the outside world. Also struggle with differences in communication, interaction often due to extremely restricted interests and mixed signal communication from the general public where people don't often say what they mean or mean what they say.
Online is where you'll see most of us; we can dip in and out as we can cope with, and can take enough time to write, edit and sift what we want to say rather than the on-demand style of irl interactions where words are difficult to form constantly.
Some of us have such high potential because we are very intelligent and have been told this since childhood but it's not easy to navigate the world and other humans. We "fail" at school, work and socialisation because of overstimulation as well as constantly either feeling like aliens among other people or being made to feel that way inadvertently by them. Some of us are struggling because we're trapped inside our bodies and wish we could move around the world easily and as expected but such is life.
You'd see me and not know any of these things until we start having a conversation (if we do and if i happen to be able to speak/say more than the cursory hello and smile) or you spend a day with me. Then you'd start thinking that something is off but won't be able to put your finger on it till you're told.
To stop the odd looks and confusing stares I get 99% of the time irl because of this, I let people know right off the bat that I'm autistic or I wear my lanyard. It helps them make sense of me and whatever they may have picked up on as odd, weird or annoying. I find that most people are more patient and understanding irl when I do this. I've seen some disapproving looks too but what can you do?!