Man this thread was a rollercoaster. Seems like you ran into some incredibly fragile egos. For what it’s worth, I switched my 73 year old dad and his business to ZorinOS (An Ubuntu-based distro designed for former Windows users to easily switch to Linux) with LibreOffice, Thunderbird, and Firefox. Granted he’s a solo shop, but he was able to pick up ZorinOS fairly easily.
Well I’m assuming if it can bypass the lock screen somehow it can pull encryption keys, or just let the user gain full access to the phone and open the signal app directly.