Student loan is very different from most (all?) other types of debt - the collateral is inside the debtor's head. In other types of loans creditors can put a lien on some type of property - cars, houses, business, etc... For student loans there is no such recourse. Student loans lost bankruptcy protection in 1976 [1]. Student loans became a crisis way later than that (I went to undergrad + master in late 90's, early 2000s and nobody was fretting about student loans. First I heard somethign about it was in the aftermath of the 2008 Financial Crisis). I think student loan crisis is a combination of out of control tuition prices, low financial education on the debtors' side and predatory marketing techniques on the creditors' / colleges' side.

[1] https://www.tateesq.com/learn/student-loan-bankruptcy-law-hi...