So stop letting the government guarantee the loans. Watch how the prices fall once only a small fraction can afford to take a $200,000 loan to pay for their college, afterwards. US colleges have been spoiled. That's why prices are so high.
I go to a research university so there are 4 main sources of funding in no particular order:
1) State funding (public tax dollars)
2) Student tuition
3) Research Grants
4) Alumni donations
State funding is down, research grants are down, and alumni donations are down. The autonomous costs of a university don't decline, so that loss in revenue needs to be made up elsewhere, thus it comes from student tuition.
More likely, you will just see the proportion of foreign students increase dramatically. College these days is already mostly made up of semi-rich kids from America and actually-rich kids from China. With loans at least some middle class American kids get a shot.