When I was a kid and teenager, I thought I'd be independent by now. Then reality hit: school is expensive. Mentally ill people who get driven out of school and go crazier don't have what it takes to live independently.
I recently turned 30, and I live with my parents. They keep back a little bit of my disability money, but that's more for me than for them. They bought me a decent car, buy me decent clothes, etc. Drives the neighbors crazy, since they used to be able to pick on me mercilessly.
Anyway...I think it really depends, blah blah blah, but the reality of the economy is...its hard to live independently. You often need some kind of degree, which usually=debt for somebody. Then you work a job at which, odds are, wages are stagnant (or falling)...if you can get a job, that is. Lots of people can't. Even if you get one, you may well be part-time or under-employed. Or laid off when things get rough :-(
I read somewhere that the old American Dream was gradual improvement in standard of living in each generation. So, your kids live better than you did, their kids do better than you, on down the line. The reality is that its harder than ever for people just to maintain a decent lifestyle, much less progress over the generation that came before them. Some European countries, thanks to carefully planned tax laws and other regulations, have more upward mobility than we do :-( .