Some time ago I spoke with an acquaintance of my. She's in her late 40s and has a son in his early 20s. Since both of us have children our conversation naturally turned to a discussion of parenting issues. She listened with fondness to my stories about experience with tweenagers that for her are already a long gone experience and then proceed to share with me her experience with dealing with twentysomethings. As is the case with so many young people these days also her son is still searching for his place in our society, partying a lot and prolonging his studies. Faced with such behavior parents used to have a simple solution of presenting their children with ultimatum to either study more diligently or to find a job. But, as my acquaintance found out, most parents no longer have the luxury of presenting their children with such ultimatum. In today's scarce job market it's already very hard to find any job for a young person without a college degree and almost impossible to find such job that would provide a decent pay and let young people become independent of their parents. So twentysomethings remain a burden to their parents in any case so it makes much more sense for parents to at least try to make them finish their degrees than to have their children idle and unemployed at home and causing problems to everybody.
I think the experience of my acquaintance is not relevant just to parents of twentysomethings but to society at large. With technology eating low-skill jobs, society is faced with an army of unemployable people with idle time for destructive behavior. It might very well be that also society at large will have to keep young people in (educational) institutions until their late twenties at all costs or risk further rise in left-wing and right-wing extremism.