In the UK student debt is only cancelled at the age of 67 or something equally silly. They're also very tenacious. They're still chasing a friend of mine 23 years after they took the loan out.
If I hadn't earnt more than the payback threshold by the age of 67 I'd be asking for compensation for being provided with a shit education.
I think the with the new system they are written off after 25 years. The threshold is 17500 pounds per year, so the average person earns about 5k more than that, so will pay 450 per year (9%).
I think people nowadays have like 50k of debt sometimes, so at 450 per year, it might take a while to pay back!