Because it wasn't people lending him that money.
Could you at least bother finding out how the current monetary system works before articulating strong opinions? Because as it is, all you're doing is demonstrating deeply ingrained cultural programming. This is beginning to get tiresome. If nobody can be bothered to actually read the evidence, complete with documentation, that one offers because it looks too much like an academic paper (which it is), then I really don't know how we're going to have a serious and honest discussion that's nor just a reiterration of those same old talking points. "PAY YOUR DEBT OR YOU SHALL BE DISHONORED, PEON!" is a mentality which serves nobody but the guys living off that tasty compound interest. You know, the same people who'll happily pay themselves a nice big bonus after just having been bailed out by the general public. Have a look at this link. Those numbers are peer reviewed. See the total outstanding amount? Yes, that's 1.54 trillion $. And here you guys are, getting worked up about how a guy defaulted on his student loans. Do I think that guy acted responsibly or that he has any right to compare himself to today's struggling students? Not at all.
Are all of you getting worked up about minor issues while the elephant in the room has just grabbed grandma and is about to stomp the couch? Absolutely.