Not cancelling student loans is also a political play, because of the securities that depend on this unpayable debt (SLABs).
https://www.natlawreview.com/article/rmbs-to-slabs-history-r...
So right now we are prioritizing SLAB investors' profits over giving consumers more spending power. If college graduates suddenly could spend their loan payment money on other goods and services, it would be great for the economy. Loan repayments have been frozen for years now and nothing bad economically has happened.
But instead we're just protecting the rent seeking of the wealthy, which isn't really worthwhile economic activity.
Personally I think SLABs are extremely unethical, but even if you disagree with that, SLABs are unsustainable and look a lot like the subprime mortgage bubble.
I agree that there needs to be something to drive the cost of education down, but I don't know if a tuition price ceiling is the way to go. I think a good start would be punishing schools that spend elaborately on buildings, athletics and excess/overpaid administrators while also paying their grad students doing a lot of the teaching work starvation wages (or if you're UCLA, don't even pay them at all!) and neglect spending directly on education and tuition. I think an endowment cap is a great idea in this area, to force schools to lower tuition by having to spend a certain part of their endowment, rather than letting them hoard money.
Some other things that are extremely good ideas is letting the interest rate be renegotiable/refinancible. For example, why did I have to continue paying 6.5% on my loan when rates everywhere else were near zero? And also letting people discharge loans in bankruptcy like pretty much every other debt.
The bubble will burst any day now, since enrollments have been declining for years at this point. Until then, the only people benefiting are student loan servicers, useless and overpaid administrators, plutocratic athletics departments, and investment bankers, NOT students or people doing the actual educating.