The benefits are actually much larger than I've just described. There's a snowball effect as the industries of the state move up the ladder. America is currently benefiting from past state investment in education. (There's intangible benefits too, but for these purposes let's just talk about the benefits the state accrues.)
That's if you accept the higher-education-as-training model. Under the higher-education-as-signaling model, the primary effect of education is to choose how to allocate a fixed set of high paying jobs. If there's 100 slots for new lawyers this year, then the difference between sending 150 and 151 students through law school is an additional unemployed lawyer.
Basically state governments off-loaded the burden of funding on the students while reaping the benefits of said investments.
Further, financial aid makes nameplate number less meaningful. If someone has rich parents or wins a full ride then schools want to milk that for as much as possible. Otherwise they can always add discounts down to whatever someone can pay.
http://slatestarcodex.com/2017/02/09/considerations-on-cost-...
My observations from attending and then later working at a large southern public university is that a bunch of things happened:
1) The financiers got in bed with the financial aid office, figuratively and possibly literally.
2) The campus went on an inexplicable building boom the likes of which no one had ever seen before. The state funded those projects, but they were clearly handouts to construction companies and pork spending. Sickening, really.
3) The quality of the average student plummeted. I blame the financiers for this, too--asses in seats is a thing.
So while it may be generally good that more people had access to higher education, at the same time the quality dropped, and I seriously doubt the outcomes for many of those people actually improved over attending community college or perhaps no college. Their debt loads had to be tremendous, after all.
It's also possible that states where education was valued have pulled back funding. There is actual hard data to indicate this is the case, but I'm also trying to avoid dismissing your claims out of hand.