They could have changed the law back to allow for student loans to be discharged in bankruptcy. This way, people who really need the forgiveness can get it.
But, ultimately, this is something Congress has to pass. It's unlikely the scheme would survive a court challenge.
The trouble with student loans, beyond the demand pressure they add to boosting education prices, is that there is nothing to repossess. Default on a home or car loan? Your home or car goes to the creditor. Refuse to pay school bills? They can't make you un-learn. It should be a high-risk loan. Lenders should suffer some risk, but instead, government stepped in to assume that debt. The loans aren't stopping. The structure that allowed this mess still exists. There is no real systemic change, because people still assume we need degrees, and college is the best way to learn.