Imagine if this was, say, at a bar. A person holds up a sheet of paper on a clipboard and says anyone can write about anyone else in the bar. Would the police be called? Would legal threats be made? People freaking out like this is not consistent with social norms. It's magical thinking about the internet somehow being different or unique.
Good luck dealing with these small minded administrators.
Bars probably don't have a directory of everyone that attends the bar, that you scraped and published without permission.
The fact that a person is a student at the school can be very sensitive information. The classic example is someone who leaves an abusive spouse/family and does not want to be found. Now their name and picture is out there, and their timetable and therefore whereabouts could be partially inferred from the school calendar by someone who knows their interests.
Yeah, but he also took students' PII and put it on his website. If someone did that in a bar, there's a good chance they'd get their face punched by others in the bar.
Any bar worth going to would kick out the asshole with the sign and ban them from returning.