If you wanted to solve the education cost spiral, the Feds need merely begin reducing the guaranteed funds, stop guaranteeing loans, or strictly lock down the guaranteed loan sums. Colleges would be forced to adjust to that new reality, in which they don't get perpetually increasing tuitions.
And if you want to check the concept, look up how much of a college education is subsidized by government loans today, versus 30 or 40 years ago - personally I think the general answer is obvious.