Everything
@Laura33 is spot on.
Here are the basic steps of how someone in what used to be a public service profession ends up over a half million dollars in debt by graduation.
1) 1940s-1960s, the introduction of private health insurance during WWII creates market and salary inflation in health industries.
2) 1970s-1980s, education in those fields remains publicly subsidized at high levels, leading to a large surplus value accruing to medical professionals. People realize this is a great gig if you can get it (high income + low schooling costs), and people pursue it in droves. "It's a good gig if you can get it."
3) 1990s-2013, schools raise tuition to capture some of the surplus that had previously accrued to graduates. Public funding is pulled back in a major way, since the public no longer thinks of these high paying professional jobs as public service. Tuition goes up more to compensate. The gig gets less good, especially in the early years, but the general public still thinks it's a gold mine.
4) 2005, GradPlus loans provide an unlimited, nondischargable line of credit to professional students.
5) 2013, interest rates on federal student loans after graduation are doubled from 3.4 to 6.8%. They have since declined some.
6) Circa 2014, the Reddit poster in question walks across the stage at college graduation. He might be the first in his family to go to college, but maybe even more likely his parents made reasonable money working in a cube somewhere that they blew entirely on a big house and leasing new SUVs. Their incomes haven't grown in real dollars for decades, so they're saving less and financing more to enable their expectation of lifestyle inflation over time. They paid little or nothing toward his college (because big houses and SUVs), and so he's already in debt 50k+. The parents don't tell the kid that dentistry used to be a good gig but it's less good now (in the unlikely event that they know), or that it's a good gig for those who get parental help, but not for him since he's on his own. Nope, instead if they tell him anything at all, they tell him to go for it and the finances will work out in the end. So he goes to dental school, and ends up funding a large portion of it with GradPlus loans.
7) 2020, the poster in question's unsubsidized undergrad loans have been accruing 5+% interest for the past five years. Plus, he's taken on $50k in tuition, plus $25k in living expenses each year during school. So, yeah, he's in for $500k+ now. As
@Malkynn mentions, he may very well be able to pay off the debt, but the next ten years are going to be tough: A small town one man dental practice in my area recently changed hands for over a million dollars.
We've been constructing this giant game of Mousetrap haphazardly for 75 years, and it's just now starting to go off.
