This is a fascinating idea, and totally obvious in retrospect :-)

I've noticed features that work towards cutting off access from global file system. Containers are mentioned in the article, but there are other things like systemd giving easy access to per-service private temp files, blocking access to /home, whitelisting paths that are allowed at all etc.

The problem really is that this global mutable state has existed for 50+ years, so lots and lots of things now rely on it: dynamic loading of libraries (could be separate objects from files), configuration (doesn't need to be stored in files), UNIX sockets that are accessed by file name etc.

And not only have many programs started to rely on files, but many have relied on them being mutable. Webservers can be told to re-read their config from a running process, things like that.

So, is there any way forward for UNIX-based systems that don't break the world?

Edit: another interesting observation is that iOS has already done away with the global file system, at least from the perspective of the apps.