If we are speaking strictly about the V20, I would generally agree with you but for the fact that eleven people from my school alone ended up in the V20. I cannot speak for other schools.
What school? A school in a major market (e.g. NYC, Chicago) can land a handful from time to time, but this certainly isn't the norm among tier 3/tier 4 schools.
Of course it's a numbers game. Someone who takes a full ride at a tier 4 school but finishes #1 in his class can work in BIGLAW and be at the same firm as someone who took out $180k in student loans at a t14. Still, I'd argue that there is a ceiling for tier 3/tier 4 grads--it's tougher to lateral, it's much tougher to move to the bench, it's tougher to move into high level gov't work, etc. It's true that some tier 4 grads do quite well; it's also true that Bill Gates dropped out of college and is now filthy rich. But I wouldn't advise people to drop out of college if they want to be rich, just like I would tell people to take a long, hard look at law school if they want to work for a big firm but will be attending a lower ranked school. There are opportunities to work as a DA, PD, or the like, but it's not like student loans scale with school rank; it's pretty easy to run up huge debts at a terrible school, too. And those need to be paid back, unfortunately, and many people won't be making a great financial decision by going to law school.