I do not have a mobile device. I work in computers and networks, and i do not need one. Everyone i talk to, even if they themselves feel the need to be connected 24/7, understands that i do not want to be interruptible anytime anywhere, or trackable, or distracted, or straining eyes and patience on tiny screens and controls, or subject to needless radiation exposure, or paying monthly fees for communication that should be free in this century. So please speak only for yourself and do not put down those who live different lifestyles.
If i did have a mobile device, i certainly would not unlock it for anyone. While traveling i would leave it at home and get a burner device either on the way or at the destination, and use a secondary email address to register it.
It isnt the police or anyone else’s right to invade people’s brain working space or private communications. You are correct to advise people not to lie and to tell them what is likely to happen if they insist on privacy. They will go in with open eyes, expecting to be held up but also able to plan ahead for the delays in choosing the high road.
When enough people stand up for their rights, queues at airports will become unworkable, and the administration will change their policy.