I added the clause: "With no student loan debt to worry about!" above. That's an important aspect, I think. They could afford to get degrees in subjects that may not have paid all that well (teaching, for example) where as now people have to consider how they're going to pay back that debt and choose degrees in fields that will enable them to do so.
> They could afford to get degrees in subjects that may not have paid all that well (teaching, for example)
I also wonder how much of that growth is from high school students being told to go to college above all else, and how this graduation increase corresponds to enrollment and graduation from vocational schools.
I do think your point is the big one: people could go into college and come out with knowledge in the so-called soft skills, like philosophy or literature (areas that don't pay well but are vital for a society to understand itself, if nothing else). Why society doesn't value teaching and similar jobs as much as it does other industries is left as a debate for another time.