Right -- but the notion that each window on your system is managed by some random process running on a random remote system, and it's all seamlessly integrated, is just not a normal idiom today.
You can run a remote window in an RDP session, etc, but it's different from X where the server may be the only processing running on the system you're sitting in front of and everything else is a melange of remote systems. Even a chromebook -- the UI is driven by stuff on the "local" computer.
With X, I can run a window manager on one host, and a mixture of random windows spread across as many remote hosts as I have open windows. Plan9 is similar, but for every other modern GUI / OS setup there's a "local first" mind set. Sure, you can do things in a totally different way but those are largely the exceptions.
You can run a remote window in an RDP session, etc, but it's different from X where the server may be the only processing running on the system you're sitting in front of and everything else is a melange of remote systems. Even a chromebook -- the UI is driven by stuff on the "local" computer.
With X, I can run a window manager on one host, and a mixture of random windows spread across as many remote hosts as I have open windows. Plan9 is similar, but for every other modern GUI / OS setup there's a "local first" mind set. Sure, you can do things in a totally different way but those are largely the exceptions.