Part of the problem is increasing social isolation, which is in turn driven by the erosion of extended families and the shift of population to ever-larger cities. Small town, neighborhood, and family networks used to provide most of the support. They still do, where they still exist, but that has become a sometimes thing.
I have an autistic nephew. I don't know where he ranks on the scale; he expresses himself well and is a great reader on a very narrow range of random subjects that trigger his interest. But has severe social liabilities and cannot handle strangers, crowds, noises, or surprises, etc. He will never drive. He is managing for himself in a small apartment where he can walk everywhere, and is working steadily in a sheltered job environment. He is a fine young man with a serious handicap, sensitive about but accepting of his condition, and trapped. His parents live nearby and keep an eagle eye out; the apartment is a recent development, and has been positive all around.
It's a tough situation. When the parents pass, all bets are off unless the older siblings or another relative steps in. This is in a small city where the pace of life is not overwhelming; I cannot imagine managing something like this in a major metro area where one is totally car dependent and both parents work.
I can relate to that. Certain sounds or noises, crowded rooms even with family talking or a sudden surprise like the phone ringing while I'm posting set me off. For some reason I have seizures from this type of events that hit my upper torso like a bucket of ice water or a cattle prod. I spasm violently from my shoulder up. On a bad day in a bad environment as many as several seizures a minute. On a good day at home sometimes none. I'm at over 50% hearing loss so sometimes taking my hearing aids out helps.
If I don't stop them fast I'm physically and mentally exhausted for the rest of the day. I do take medication to control it somewhat but it makes shopping difficult. That usually gets done at night.
I still drive and will do so until it moves into my arms or my sensory system makes doing so unsafe. First experience with this had me on the interstate no knowing where I was, where I was going, why, how long, etc. I drove the darn stretch regularly. I can now head that off long before it gets to that point with medication.