I certainly do not know what my friends are doing 24/7, perhaps not even within a day or two. And that's plenty of time for law enforcement to install a third-party client on their phone, or just read the messages. I agree that having it is better than not having it, but I would not put too much faith in it being useful against law enforcement. Perhaps retracting a mistakenly sent message, but not much more than that.
I feel like you're being needlessly dense. The threat scenario is being at a protest with your friends, not some midnight abduction. And I'll I'm arguing is that it is better to have it than not have it because there's a __chance__. When it comes down to it every aspect of security and privacy is probabilistic. Security walls aren't impenetrable, but unlikely to be penetrated in a given time-frame. If it doesn't reduce the floor on security or privacy but increases the probabilistic upper bound, why not? So my complaint to Signal is why shoot yourself in the foot by limiting this to 1 hour? (24 if you run a custom app)
There's a reason big companies/government employers want root access to your phone and will wipe data if it is lost or stolen. Because it reduces the chance that company/state secrets. No one thinks it is a guarantee. But if given the choice of "revealing a secret" vs "rolling a dice to see if I reveal a secret or not" I'm going with the latter no matter the odds.
