Someone has to be the legal guardian of kids, until they become independent. In our society, it has been chosen that parents are the ones. They usually take this duty to unfortunate extremes, and try to "instill their own values in their kids", etc.
So, there has to be a point where the legal guardians are FORCED to finally let go.
So, logically at that point, there has to be an arena where kids can truly learn independence. Work is not independence, so I don't accept your solution. College is it. I'm satisfied with our setup. Learning what it is to be free is valuable, so I reject your initial hypothesis.