This is really hard to do in practice: for example, if you block YouTube.com you just broke a ton of lesson plans which rely on students watching things like scientific materials from NASA, HHMI, etc. It turns your approval process into a source of political blowback unless it’s really fast, and it’s usually not a good idea to be in your users’ minds negatively all the time.

I'm pretty sure we'd still need to break TLS. Domain-level just isn't granular enough.