While this thread was originally dealing with undergrad student loans, some have mentioned grad, law, etc, loans.
Big undergrad loans are different. They’re often emotionally-based, and made with the decision-making skills of a 17/18 year old or a guilt-ridden/indulging parent.
Grad school loans are another story. The student is older, and hopefully less impulsive. At that point, s/he should be more aware of future likely earnings. But, that doesn’t mean that there aren’t some poor decisions made for grad school and professional schools as well. Upthread someone mentioned a nursing student who now has big grad school loans (not NP). I know a new BioMedEng’g MS student who opted for “full loans” at one school over a “free ride” at a nearly comparable school. His new salary is NOT what he expected, so his loans will be a struggle. We are seeing new law grads with huge loans who are barely earning $50k per year…and many are unemployed.