The prohibition was retroactively applied to private loans already existing.

My wife and I chose private loans specifically to retain bankruptcy protection in case of serious life issues. A couple years after we took them, the law changed and we were stuck with the higher interest rates of the private loans without those protections.

For a time, we considered a Constiitutional challenge to that, as we believed it to be an ex post facto law. We didn’t want to incur the negatives of a bankrupty to gain standing, though, and couldn’t afford the astronomical legal fees that would certainly accompany that sort of case. As far as I know, no one has pursued it.