My comment was specifically about the question of morality, not about whether it's a wise business decision.

I think you both are a little bit right.

If you are in a casual agreement with a friend and don't keep up your end then it's immoral.

If you have a contract that specifies expectations and consequences, then it's just a business deal.

The (predatory) school loan business works from contracts and they are obligated to keep up their side only as much as you are yours.

The real immorality is not accepting the consequences embedded in the contract to which you both agree to, it is that the United States has such a business in the first place.

Well actually second place I guess. When the student loan business started it was not predatory. But it got horribly abused, by the borrowers who would declare bankruptcy gaming that system, schools who raised rates because they knew loans were available, and the lenders who astroTurfed children into believing that it was a good bargain to exchange $200,000 at high interest for a Art History degree