The clear result of this would be parents that can afford to send their kids to college will send their kids to college by just paying for tuition. Interest rat

The clear result of this would be parents that can afford to send their kids to college will send their kids to college by just paying for tuition. Interest rates will go up significantly, which makes the math on taking out a loan worse for anyone that doesn't need one. It would be a death spiral for loans. I'm not convinced the politics of subsidizing education get better after that. There's a very high risk that a large and powerful swath of the country reacts to it with "I worked my ass off to pay for my kids to go to college, why should I subsidize yours?" The resulting increase in inequality is bad for society as a whole, but honestly it's a feature for most upper income parents. It would probably put some pricing pressure on college, but the predictable knock-on effects are really really bad.