How was it dumb?
You have a generation of Americans who were told repeatedly and often in their teenage years that if they wanted to be able to compete in the global job marketplace, they'd need, at the very least, a bachelor's degree.
As it turns out, employers were going to offshore those jobs and cut those wages regardless of your education. The value of degrees was wildly over-inflated compared to the economic reality, particularly after the Great Recession and COVID. The result has been an entire generation of people who aren't able to attain the same life milestones as their parents' generation, which is inherently destabilizing to a society. Corinthian Colleges wasn't the main perpetrator of this; the entire system was. By their shutdown in 2015, most people born between 1980 and 1995 were out of college and were paying massive loans to legitimate schools.
When you have a party (in this case, the federal government) obtaining something of value (student loan interest payments) via statements that are materially not true, there's a word for that: fraud.
Student loan forgiveness was a targeted effort on the behalf of a lending institution's head officer - in this case, the President of the United States - to try and renegotiate the terms of the loan serviced by that institution as to give some remedy to the problem.
This would have required a write-down of the foregone payments that would be approximately equal to what the US government spends on providing OASDI checks to retirees for one year, and most retirees do not rely on OASDI checks to avoid homelessness, starvation, or other destitution. It's basically a bonus that you get for living over the age of 65, at this point being paid in part by loans taken out by the US government that will have to be paid off long after the recipients of that money are dead.