The problem is when that same specific place also only allows that form of communication-- no cell phones, no portable computers or gaming devices, just computers with limited activities. And there's no reason for any block in particular, just up to some unknown deciding entity.

But in general I agree.

The main difference is how we read this, I think:
I'm not saying I approve of blocks/filters, or that they work well. I'm saying that if someone is providing a service, they have the right to provide it on their own terms, and that should be respected.
The problem is that the filters aren't equivalent to the "someone". Instead, it's a third party that those immediately responsible (teachers, bosses) do not control. Depending on the teacher, different sites may be allowed, and that's where I think the decision should be.
But having a common system is simpler, if not smarter, so I guess there's at least some logic in that. And it means less work for the teachers...

While, yes, the thread is off topic, I think the original question is answered (more than answered, now).

To Citrusbytes, feel free to reply and make this on topic again if you have any more questions.