Do other countries allow nearly everyone who wants to attend to do so? In the US, while you can't necessarily go to whatever school you want, pretty much everyone has multiple choices of schools they can attend. Even people with Down Syndrome are now earning bachelor degrees. Not special programs for those with learning disabilities but degrees in regular programs. If they're able to pay, they're able to attend. Since most of this is financed via student loans, living expenses are covered too regardless of if the student has any realistic prospect of ever paying off the debt.

This is consistent with the top-level response, about expense signaling quality.

Consider the quantity of people coming from outside the USA to study. It may be that foreigners looking for prestigious schools are searching in the USA because their own system is middling (except maybe for a flagship school?). Thus, they're also doing the damage to the USA's education market while not affecting their own domestic one.

US does guaranteed loans which guarantees high prices. Other countries build a public university and charge little which keeps prices down.

The US typically helps people afford expensive things, insulating people from rising prices.

Other countries typically regulate prices, preventing things from becoming expensive to begin with.

This applies to education, health care, housing, and more.

Wealthy progressives in other countries put their money where their mouth is. Wealthy progressives in the US only pay lip service to progressive values because they only support wealth redistribution when it's being done with other people's money, then they magically flip and become some weird hybrid mercantilist-nationalist conservatives who insist upon privatizing gains, but only up until their brilliance fails them and they need to come beg the US taxpayer for handou- err... bailouts, emphasizing the values of the collective good as justification for forcing the rest of us to socialize their losses.

This is why Ivy League schools have endowments larger than the GDP of some micronations and are financially being run like hedge funds, while still simultaneously being supported with US taxpayer money. The progressive orthodoxy does not hold these institutions accountable for institutional greed and selfishness because of a shared cultural affinity between progressive politics and higher education, and because all of the negative externalities of the spiritual sins of selfishness and greed at institutional scale are forgiven for the virtue of being a nonprofit under the idiosyncratic, dogmatic priesthood of progressivism.

The US doesn't have progressives. We have conservatives and conservatives LARPing as progressives when it's financially convenient for them.

On a related note, this is also why Canada and the UK can make single-payer healthcare work and why the US can't. Some of those shadowy GOP dark money donors are the same faces that the public would associate with progressive thought leadership. They're following a Machiavellian playbook where they attempt to portray themselves as publicly virtuous while remaining the same soulless, greedy multimillionaires or billionaires that instinctively think from a place of unadulterated self interest behind the scenes.