Actually it is. Easy credit and the sentiment that any degree will pay off in the long run have inflated tuition prices to the point where they are not necessarily worth the investment. Similar to the house that was worth 600k and is now worth 300k the degree that costs 200k doesn't meet that value. It could potentially be worse than the housing market because there is no asset, just a piece of paper. Just like you said you can't buy and sell college degrees.
The point here is that banks are starting to get it. Just because you can't walk away from student loan debt doesn't mean you have to pay it. Sometimes the numbers just don't work out. The odds of someone with 400k in student loans from a PhD in Philosophy paying them off in a lifetime with their job is a barista are very low.