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.
Installing apps is the trivial part; isolating, or removing / reinstalling user data is much harder. Especially a few gigabytes of it. An SD card could work maybe.
This all goes against the grain of the smarthpone UX, the idea of a highly personal device that you can use for anything, and might need (or benefit from) at an arbitrary moment.
If the point is reducing e-waste, the solution would rather be opening up the hardware enough to provide long-term software support, LineageOS-style.
In general no one wants to share anything with anyone, but when two people cannot afford a device individually, but it is within reach when they buy it together, time-sharing becomes a totally acceptable solution.
> Installing apps is the trivial part; isolating, or removing / reinstalling user data is much harder. An SD card could work maybe.
Checksums might overlap by quite a bit. No need to remove programs installed by both users. If the total installation of each user is 10 GB, but the installation diverges 300MB only, not a big deal in most cases.