I think that AI generated porn is fine. I think that AI generated porn of specific people who did not consent is bad. "High schoolers creating porn of their classmates and distributing the results" is an abuse that a huge number of people already are forced to endure, and it will only get worse. Nobody should have to deal with that.
The real problem is the "distributing the results", but in most schools that’s treated as a serious offense. 20 years ago you could swap faces in Photoshop and it also wasn't a big deal. Ultimately, it’s the school and parents that must set the limits, regardless of the tech.