Many other countries besides the USA have lower tuitions and lower per-student debts. Why? Government support for education.
So let's start with your last item first - do you imagine the U.S. Government, and state governments, DON'T support education? How much money does each state pour into state and community colleges? Acvording to you, nothing.
You know what the difference is between all those "free colleges" in Europe and elsewhere and US Colleges? The vast majority of foreign "free" colleges are run by the gov't, enrollment is limited, and students get in based on merit. In America, the vast majority of colleges are privet, "non-profit" institutions, and they admit almost anyone willing to pay the tuition they charge, usually with money they hope to earn after they graduate.
If you want to compare apples to apples, let's compare "free" European colleges and state colleges, let's not compare them to private colleges.
In America, any student can buy their way into college with borrowed money, and somehow that's unfair. Fine, let's stop government secured student loans and make all state colleges 'free, but merit-based', let's stop offering remedial math and reading classes... let's be just like Europe, and anyone that can't earn a spot at a free state college is free to find the money privately to attend the local 'non-profit' schools. Is that really what you want?