We like to at least have the allusion that you can start anywhere on the socioeconomic scale and end up better (sometimes far better) than you started. Education has long been one of the best ways to increase your lifetime earning potential, and having the government backing allows someone who had little growing up to receive the same education as the kid whose parents are paying for everything, and to go as far in life as they possibly can.

There are obviously holes in this narrative, but we like telling ourselves this can happen.

While there's not enough value in 17th century art history for the US to graduate 200k scholars per year and expect in-field employment, there is value to society in general to not losing our history and learning more. Letting the banks decide who gets loans will instantly mean those who can't pay cash cannot pursue that education or need to go on cheaper routes for college. They may or may not be viewed as a comparable education and quality candidate.

I'm not a fan of our current system, but a purely utilitarian system I see proposed seems likely to continue the spreading the social divides between the rich, middle class, and poor.

I'm an advocate for cutting a lot of the unnecessary fluff and expenses from college. Administrative overhead is excessive. Dorms are way nicer than they need to be. Alas, other colleges have nice dorms, so a single college choosing to go cheap on the dorms will probably decrease admissions and thereby revenue.