Maybe, wouldn't something like a Faraday bag work though? Then you don't even run the risk of someone trying to twist the meaning of whatever regulation might exist to try to charge you with something.

That is a point, could someone even do that on something classed as a phone though? Don't most places have some kind of law about these devices always being able to reach emergency services like 911?

It seems like it'd be relatively simple for a bad actor to record something and just... wait until you had a data connection though wouldn't it? Seems like it'd be more secure to just keep there from being any data to send rather than relying on a bad actor not being able to send it. Am I missing something here?