You seem to have a greater concern with who pays for education than you do for its macro-level effects. You simply don't think its the function of society to provide an education, even though it is society exactly that reaps benefits from it. These macro-level benefits to an education don't stop at high school graduation, even though the U.S. stops paying for it at that point. The demands on education are pretty much the same in (developed countries) worldwide, but the U.S. system of unsupported education causes overvaluation especially when student loans are government-guaranteed and so easy to get. Since the last few generations in the U.S. have been smaller due to decreased birth rates, colleges & universities have met increased competition for smaller student populations with fancier facilities and amenities. They show no concern with price sensitivity of students because demand for college education is pretty inelastic, close to that medical care and students can always get loans. Actually affording the debt service on those student loans is another subject, though.
So if education is undervalued in the European model, and overvalued in the U.S. system, perhaps it just a matter of finding out which system properly values education? Currently, the U.S. system is seeing runaway inflation in education costs, isn't it? How does it serve America to have such education this expensive? In the 1970's, its possible their model was sustainable but once demand was cut by subsequent, smaller generation size, and the supply of colleges stayed the same, its pretty easy to see how unsustainable this is. The European model simply remove education from the job qualification equation, much as the developed world has done for health care, for instance. You certainly need to be at a certain level of health if you're going to be employed, so developing countries at the start of the 20th century made great investment in public health to cut the communicability of disease with public health infrastructure around inoculations and early detection of epidemics, etc. Think of the impact of diseases such as Spanish Flu and later, polio. Much of this public health investment was done to preserve the stability of the workforce, and less so out of humanitarianism. But, of course, the workforce support society and humanity at large, too.
The only hope for many Americans paying student debt in their mid-twenties (and beyond) is the inheritance they will receive from their boomer parents. While I am not quite that young, I do know many that are factoring inheritance into their retirement planning.