This is my experience. I have very high flying cousin who is now retired. Amazing with computers, had a top job. No diagnosis but always struggled with communication, rigid habits and eating, and had speech therapy when young. Struggled in primary massively, but started to blossom from 14 when he discovered computers, which were very new then. No real friends but seems happy, has a massive income, and spends his time hiking and online talking about very nerdy stuff.
His son, his parents never got married or lived together, had help at school, also had speech therapy. Diagnosed autistic. Not academic at all. Got a trades job, is good at it and makes good money. Works as part of a team as he can't communicate really with customers, but does a great job. Had help of parents to find somewhere good as got bullied in first job by colleagues. Owner of firm now makes sure that doesn't happen. Own home and spends remaining money visiting car shows which he is obsessed with.
My own father clearly autistic, no friends, rigid thinking. Did various jobs, had a family.
My brother, again clearly autistic, zero school support, struggled a lot at school. Worked in computing, got married and had a family. Again no friends. Coming up for retirement.
There was far less support in the past and yet the older generation largely did get jobs, many got married and had children. They may not have achieved as high paying a job as they may have been capable of with support. But they managed to work and live an ordinary life.