YOU ARE A FIRST CLASS IDIOT, if you believe even HALF of what you've said on here. Autism is REAL, pal. And NO, it's NOT an "illness". People with Autism Spectrum Disorders aren't "sick" in the traditional sense of the word. Instead, Autism is recognized as a DEVELOPMENTAL DISABILITY. There's a BIG DIFFERENCE between a DD and someone who has an infectious illness like the FLU, and you should understand that much at least.
Autism is NOT CAUSED by poor parenting. If that were true, those of us who have the HIGH FUNCTIONING version of it (which includes me) wouldn't be able to do even HALF of what we do every day. I have a college degree, and I live completely independently. My parents live hundreds, if not THOUSANDS of miles away from me, in other states. I keep in touch with them by phone and by email or text. I work full time for a state agency which SERVES people with developmental disabilities like Autism. I also drive my own car, pay my own bills, and lead a "normal" life by most peoples' standards. And this is true despite the fact that I endured YEARS of abuse from my parents, my peers and the school officials while I was growing up. It wasn't until I left home to attend college that at least some of the abuse finally ended. After college, I went to work in one of the most cutthroat industries around, and stayed there for over 20 years, leaving only because I needed to find a more stable line of work that would allow me to save for retirement.
Why was I abused growing up? It's because I was "different" than the people around me. I thought differently than they did, and I was a natural loner, although I didn't initially make that choice on my own. It was forced on me. People who end up as loners the way I did seldom if EVER choose that path on their own. Instead, we become loners because we LEARN, QUICKLY, that we MUST stay alone and away from other people if we want to stay ALIVE. Loners aren't stupid, pal. What we are is people who are BADLY misunderstood, and often badly MISTREATED and abused as a result. My having high functioning Autism doesn't mean I'm stupid. I have a normal IQ. But there are far too many people in America who view anyone who has even the smallest sign of any kind of disability as "different" and therefore, they consider people like this to be "unacceptable" and a THREAT. That's WHY people with Autism are so heavily STIGMATIZED in America.
Autism isn't just one disorder. It's a WHOLE SPECTRUM of disorders. Some are very mild and produce few if any symptoms, like mine. Others, however, are severe, and cause serious impairment in those who have them. The young man you saw was likely on the severe end of the spectrum. And judging from what you said in your question ( which is really more of a RANT against people with Autism) I suspect that the young man probably has a pretty significant INTELLECTUAL DISABILITY ( what they used to call "mental retardation" before that language was outlawed in 2010) along with the Autism. ID and Autism CAN AND DO occur together- and Autism is considered to be a complication of ID. And NEITHER condition is the result of poor parenting. The young man in your question lives with his dad because he's incapable of living ALONE. He doesn't have the mental capacity to handle his own affairs, and it's likely that he never WILL. And no amount of "tough love" will CHANGE THIS. You can't cure Autism or ID by being "tough" on someone who has it. This young man is actually LUCKY that he has parents who are able to care for him. There are far too many adults in the US with Autism who don't have this luxury.
One other other note: there are plenty of examples of famous people who have Autism around. Bill Gates, who founded Microsoft, is one such individual. The late Steve Jobs, who co-founded Apple computer, is another. There is evidence that the current occupant of the White House is a third example. And I can think of several more people who have it and who lead completely normal lives.