> I assume that means he is blocking certain parts of the US, if not the US in its entirety.

On what basis do you make that assumption?

It is still the internet, routing issues can and do occur. There is absolutely nothing in the configuration of my server(s) that would block anybody from any nation.

I'll alert my hosting provider to make sure they know about it just in case it's a novel thing and their monitoring didn't pick it up yet but it could easily be further upstream.