If you decide to pursue a MFA in French medival music and accumulate $200K along the way (a real-life example, btw), student loan debt can be a bit of a problem.
If all you can afford is a Yugo, but the government will give you a loan to buy a Ferrari, don’t blame society for your debt.
Choose your degree wisely and the amount and type of debt to finance it, and student loan shouldn’t be a problem.
If, by some miracle, education becomes free, it will result in many more deciding to go to college. Maybe twice as many as currently. There are about 4,000 univerities in the U.S. there is no way that would jump to 8,000 anytime soon. What is going to happen is the tuition would go up. The more affordable you strive it to be, the less affordable it will. Given the limited capacity, and given that the government would be paying the piper, the access would be then rationed by the government.