It would be a net good if the people who went to college were changed in such a way that they stopped destroying value and started creating value. That is to s

It would be a net good if the people who went to college were changed in such a way that they stopped destroying value and started creating value. That is to say, if college (more often than not) turned criminals into saints, and turned a welfare recipient into Erdos, then it would be an excellent investment for society. But there's no evidence it does this, and it doesn't even do a better job than high school. You can learn more on youtube than you do in college. So until then, it's a marketing racket that transfers state money into a few private hands- and the gov't goes around collecting for decades.