If the only significant amounts repaid are from those who are "successful and wealthy", get it by taxing them more, and stop loading all those who aren't with burdens of debt.

There might be a few among those "successful and wealthy" who didn't go to university, but by definition they can afford to pay. Not going to university and starting work earlier will have been part of the reason they made it big, so they benefitted just as much as if they'd gone to university.

Going to university should be about developing yourself as a person, not about building a career. Very few of the things I was taught either at university or for that matter school ever proved that important in my work. What my years in the education provided at most was to help make me the person I am, including my ability to learn on the job.