Right, and there are ways you can consider the validity of either method, but to block SMS would mean blocking voice.

Perhaps a temporary data hiccup might be a more realistic solution (or simulation, if malicious) versus "Call cannot be connected".

I think a state actor could filter at will, since they could MITM the connection and pass stuff through selectively. Not that I can see why they would bother. Although I can't see why they would take this action at all, which is why I don't believe the story in the first place.

Pretty much, agreed.