As a matter of user experience, rather than implementation, the 'filesystem' in iOS is just an app. It's one way to handle data sharing and transfer between apps, but it isn't always the best, nor is it the main one.

This has some tradeoffs, everything does, but I'm glad someone is exploring the OS space without considering filesystems as we currently understand them to be an inevitable part of that.

I can imagine an object capabilities framework, in which a 'filesystem' is just an object which owns data, organizes it in the familiar way, and shares capabilities with other objects, being quite useful and powerful.