Once upon a time, somebody, probably one of those evil goblin bankers from Gringotts, thought it would be a good idea for students to finance their education with debt. We know they were evil* because they got the government to (1)guarantee most of the debt and (2)permanently enslave those who could not pay.
This led to a vast proliferation of for profit colleges, and others, like law schools, not officially for profit but rackets nonetheless. The result probably should have been predictable: an army of heavily indebted young people ($1.2 trillion or so) who mostly lack skills in enough demand to allow them to pay back those loans. Consequently, they are poorly positioned to start a family, buy a house, found a business, etc.
Of course many of these students got degrees in subjects that ought to be reserved for the independently wealthy: art, theater, philosophy, classical literature, ethnic studies and so on. Chat up your waiter next time you go to a mid level restaurant. He or she probably has a PhD in French Literature or an MFA in some damn thing.
I got my PhD (physics) at the height of the 1970's physics boom - that is, shortly after it became clear that there were way too many physicists and anybody with any sense decided to study EE or become a hippie drug dealer. After I graduated, PhD production plummeted for a decade or so, but physics departments eventually figured out that they could replace no longer gullible Americans with foreigners. Thanks to research and teaching assistantships, though, we were mostly debt free.
I and my classmates all eventually got jobs, though hardly any in the one area we were actually trained for, university professorships. It turned out, at least then, that physics PhDs usually had some useful collateral skills.
It seems now, though, that even this century's golden ones, PhDs in computer science, are seeing declining salaries.
Education is no longer a sure fire path to a comfortable life, but it still seems better than most of the alternatives. *If further proof was needed.