Compare to other cultural institutions, like religion. When religion receded, it wasn't "unbundled." It just receded. The belief in God, the community ties, the source of leadership, the welfarism, moral support, etc.
Same for tribes, villages.
There was a Louise Theroux line about Scientology. Dissident scientologists tried to continue the practices, without the totalitarian cult stuff. It didn't work. All that was left was some squishy, gimmicky, self help stuff that people quickly drifted out of.
That said, change is coming. College is no longer a very good way of being educated, and in the US, the price is crazy high.
What still locks college I to place is that it works for the upper classes, and for the high achievers. They pay less, get more and have the most cultural influence.