Every single smartphone on the market uses internet-based storage as tertiary storage. You can absolutely do data manipulation on these data stores independent

Every single smartphone on the market uses internet-based storage as tertiary storage. You can absolutely do data manipulation on these data stores independently of client device operation, and most do (photo resolution downgrades being the most common I am aware of). And I agree about the plumbing, but this is a discussion around the environment of primitives commonly available, and I'm merely pointing out that richer environments than posix have already failed out of the market once.