I suspect it's a needed trade-off between security and practicality. I have no idea how "needed" it is though, can someone shed some light on this? Also, couldn't Signal add their own encryption layer?
* Non-technical users either won't use it, or will use a weak key
* Technical users are better served by making sure their device is secure and hard-locked with a strong passcode (tip: 5 presses of the lock button on iPhone wipes in-memory encryption keys, essentially exiting "AFU mode")
Is this the same thing as holding down the lock button and one of the volume buttons on one of the newer iPhones? I'm referring to this doc: https://support.apple.com/en-us/HT208076
"If you use the Emergency SOS shortcut, you need to enter your passcode to re-enable Touch ID, even if you don't complete a call to emergency services. "
But I temporarily enabled it now to test. Maybe I am pressing the power button wrong but rapidly pressing it five times does not prevent it from allowing FaceID to unlock the phone. Whereas power plus volume up button does indeed.
Btw, when I normally have FaceID disabled from unlocking the phone, does it wipe in-memory encryption keys when locked with a single touch to the power button or not? I was assuming that it did, but I realized now that this assumption might not be correct.