But mail and phone were essentially the only methods of long-distance communication. The new methods of long-distance instant communication are not just groundbreaking for organizing legal business.
Something really has fundamentally changed with the introduction of instant encrypted messages. I'm for that change, and against the government attempting to ban it.
it's not like you can't implement encrypted comms over mail and phone in the first place. people with a strong enough incentive (and nerds) have been using symmetric encryption for a long time.
what has changed is, like you say, how trivially easy it is to send instant encrypted messages. what was once the domain of spy agencies and organized crime is now practical for my mom to ask me what I would like for dinner. one wonders why the FBI finds that so concerning.
Something really has fundamentally changed with the introduction of instant encrypted messages. I'm for that change, and against the government attempting to ban it.