You state, it's Signal's weakness. It's not a Signal's problem anymore. And Signal is fully on our side in this. What people can't understand, is that the "problem" would not even exist in the first place if bootloaders were not locked. People would just sideload Signal or signal's clone and continue livinig, not even thinking for one second what the government wants this or that.

People gave away control over their phones - this is the main source of this problem. Everyone is trying to go around it, instead of changing it.

Jailbrake your iphone, unlock your android, and no government will have power over what apps you can use. It's THAT SIMPLE.