The problem with this is that's not why most people go to universities. The top reason is probably credentials for employment (most people stop taking classes after getting a degree), and below that is probably education for employment (if I see someone with a degree taking a class just for the education, it's usually related to something they want to do for their job).
Universities are aware of this but pretend that's not the case, which is problematic. It'd be like if grocery stores started pretending their purpose was to provide an area for debate, and every time you wanted to get a gallon of milk you had to both pay for it and argue with the cashier about politics for 5 minutes. You don't want to do that? What, are you afraid of being exposed to new ideas?
I don't mind discussing things, but sometimes you just want a gallon of milk (or degree). Of course, you could go to the convenience store down the street, but they only carry cheap milk powder.