That is not as clear cut as you make it. There have been rulings in the last several years that have allowed some private loans to be discharged in bankruptcy proceedings.

> In January 2020, the U.S. Bankruptcy Court for the Southern District of New York discharged over $200,000 of student loan debt for one borrower. Then, in August 2020, a ruling by the 10th circuit federal appeals court based in Denver, Colorado eliminated $200,000 for a Colorado couple who held 11 private student loan accounts. And in September 2020, a judge for the U.S. Bankruptcy Court for the Southern District of New York ruled to enforce a prior bankruptcy discharge of a borrower’s $400,000 of federal student loans that a servicer had failed to carry out.

> These decisions could serve as a precedent for future bankruptcy cases involving student loans, says John Rao, an attorney with the National Consumer Law Center.

> "A lot of people, even some of the lawyers who represent consumers, thought for years that you really shouldn’t even try because there's not a chance you’ll win, but I think everyone is looking at it now with sort of a fresh look," Rao says.[0]

[0] https://www.nerdwallet.com/article/loans/student-loans/stude...

Granted, this is getting very close to "the exceptions prove the rule." :D And this rule is spelled out fairly directly to be as hard as possible to discharge.