Given that swappable storage already exists in a standardized form factor at a tiny size, what are the truly functional components of a phone that should be swa

Given that swappable storage already exists in a standardized form factor at a tiny size, what are the truly functional components of a phone that should be swappable? All I can see are screen, memory, CPU, baseband mobile communications, wifi, bluetooth, camera, local sensors, battery. Observations: trying to put memory and CPU across disparate modules on the same generic block-linking bus used by the other components smells like a recipe for pain. Sensors and wireless connectivity are stupid-cheap and therefore largely not module-worthy, they would probably be on the same unit as the mobile comm's baseband. Conclusion: Maybe retry with [cpu/memory]+[camera]+[comms]+[screen]+[battery] Gotchas: Hardware profits lower, so where's the commercial carrot? I suppose a cabal of governments (EU?) or a single big one (China) could regulate heavily against throwaway devices entering their markets, which could provide enough push, though it would be hard for China to regulate. Software experience polish would suffer. Overall bulk would likely suffer, though we've already reached too-tiny-to-hold-is-the-problem so that's less of an issue.