And, let's say you're earning $100k right out of college, you have to account for what you would have earned and been earning after 4 or 5 in the workforce. That might easily be $60k or more for those particular people.

So, there would be something like $200k of foregone earnings compared to something like $50k of student debt + interest. When you're earning an extra $40k it takes most of the next decade to break even.