My Android phone prevents me from recording phone calls at the request of my carrier, even though it's totally legal for me to do so in my jurisdiction.
I'm not loving where this is all going.
Why not two people share a device, and when passed from one person to another, delete applications and install all apps and profiles from scratch using verified checksums saved on a blockchain. An OS which could do that is something like Nix. When passed to the previous person same thing, delete and install everything from scratch.
Using smartphones in a smart way, not a dumb way, like timesharing mainframes of the past. Same procedure could be applied to cars and other devices.