It seems to me we had this figured out at one point. I went to college in the mid-70s, and while it wasn’t free, my parents were able to put three kids through college with no scholarships, grants, or loans. In other words, college was affordable. Before that, an entire generation of GIs got a college education for free, which gave us 30 years of unprecedented prosperity, not to mention world leadership.
I don’t think the idea was ever “Everyone has to go to college.” The idea was “It’s best for the country if everyone who wants a college education can get one.” Until the early 80s, we believed that education was an investment in our country, so we made it happen.