That's interesting. Genuinely interested in how you can have desktop Linux pcs managed as effectively. I would love it if institutions in the U.S use Linux for their desktops.
You could configure certain DEs in a kiosk mode. I don't know much about it, but it reset the session and user to a default at every log off, he could track usage time, do all sorts of remote session management.
If you search for Linux for classrooms there are probably a couple projects still around.
I'm sorry, I didn't go into it back then. And we're talking like 15 years ago. He doesn't even own the cafe anymore (what with smart phones and all), was a repair tech for a while, and now I don't know, we lost touch.
Nope, the concept pretty much vanished after we started carrying the internet in our pockets. Even LAN houses (as in places for gaming) are gone, but I can't identify a clear reason for those.