It’s really “Everything has a File Descriptor”, nothing about the concept of a file has changed.
It's in essence no different than OOP or actor model or what have you.
I’m sure there’s an isomorphism that could be drawn but it does nothing to show that it’s an equally good paradigm to write software in. IMO, it’s a tortured abstraction.
This is akin to how shell piping in Unix is also just... text and bytes. This is limiting and produces many ad-hoc protocols.
But take what Plan 9 was trying to do, and add to it what Microsoft's PowerShell tried to do, where you stream objects, structured information, instead of just bytes, on the way in and out of commands and files...
And suddenly... we got ourselves an Erlang.
Many perfect and awesome systems have been built that never saw significant adoption.
I agree with ESR's observation: "Plan 9 failed simply because it fell short of being a compelling enough improvement on Unix to displace its ancestor. Compared to Plan 9, Unix creaks and clanks and has obvious rust spots, but it gets the job done well enough to hold its position. There is a lesson here for ambitious system architects: the most dangerous enemy of a better solution is an existing codebase that is just good enough." Source: https://www.catb.org/~esr/writings/taoup/html/plan9.html
Another amazing OS that never caught on was BeOS: https://en.wikipedia.org/wiki/BeOS Neal Stephenson's description of BeOS as "fully operational Batmobiles" is accurate and it is sad that BeOS did not become more mainstream. See https://people.cs.georgetown.edu/~clay/classes/spring2010/os...