And _not_ living in one of the top 20 metro areas is also hardly an edge case.

And even in most of those metros (OK. Leave aside Manhattan), not having a car tends to imply a lot of lifestyle choices in terms of activities, visiting friends outside of the metro, etc.

There are certainly people who are OK with living like they did in their urban school for a few years after graduation. But that's not a long-term solution for most people.