An UI would be fine, but having no permission to access ~/ is a terrible default. It causes a lot of breakage and glitchiness because applications are simply no

An UI would be fine, but having no permission to access ~/ is a terrible default. It causes a lot of breakage and glitchiness because applications are simply not written with that limitation in mind. This is why Flatpaks often crap out. It will cause a huge amount of applications / binaries to crap out if it became the default in NixOS, and lord knows NixOS has enough sharp edges already. The best solution would be a framework akin to macOS that pops up 'allow application X to access folder Y from now?' in the UI or in the CLI as a terminal prompt whenever an application tries to access a folder. With a special permission for "full home access" and "full disk access".