Take a look at GrapheneOS.
There are already: GrapheneOS (only for Pixel phones) and /e/os for example.
3 Vaults:
- my personal vault with daily notes, book notes, recipes, notes about current special interests
- work notes with cli commands, code snippets, project notes
- a shared vault with my husband with notes about travel plans and shared hobbies
And in anarchy the strongest will be the winner, so you still can have this outcome.