Are you suggesting that the art history professors should work for substantially less? That the classes should be taught in substantially cheaper (both to build and to maintain) classrooms? That heating, air conditioning, electricity, and possibly running water should be cut from those classrooms? That art history students not have access to other campus classes or facilities or resources?
Because if you aren't, then what you're suggesting is that students in other majors should pay extra to subsidize the art history students and others whose major isn't worth the cost of a university education.
On a fundamental level, I agree that higher education shouldn't cost so much, but you'll have to speak to the government about that. By pushing every single person toward getting a college degree and providing them what is essentially a blank check to make it happen, we've massively spiked the demand side of the equation. What happens when demand goes through the roof and supply is left hopelessly far behind? What's worse, normally the market for education could correct by pricing some people out of it, but in order to further the goal, the government has provided a means by which anyone can get virtually any level of funding for any sort of educational goal (whether or not it has any chance of ever paying for itself in the lifetime of the student). Thus, an art history major can get loans exceeding that of most home mortgages with no income and little income potential.
Want to fix the costs behind higher education? Pull all government subsidies for students and redirect that money to colleges and universities with a history of successfully educating students (e.g. job placement percentages, 5/10/20-year outcomes for alumni, etc). Further, erase the legal absurdity making student loans the hardest of all loans to kill. That's the other half of the problem. Finally (and this is the hard part for most people), accept that quite a number of low-income students will find some or all higher education out of their reach. This can be partially offset by directing some of the aforementioned subsidies toward apprenticeship based learning (e.g. pairing young adults up with electricians, plumbers, etc).
And what does that do? It spikes the supply side of the education/training equation. Suddenly there's more supply and it's cheaper to do it than it would be with no forces acting within the market. That brings down the prices while incentivizing higher performance for the institutions (who have zero incentive now beyond whatever sense of benevolence exists at each college or university among the staff). It doesn't bring down prices to the point where everyone can do anything they want, but that's a fantasy anyway (as some are starting to grasp). Sure, you can push everything through higher education and they can do whatever type of studies they want, but many if not most will end up in crushing debt for decades unless they've chosen something with extremely high earning potential. And if (as you state) the purpose of higher learning is not simply to make more money, then we're doing it wrong.