I think it's the smoldering ruins of the OS vendor self interest collapsing in on itself.

There's not a single good universal UI. The best is the browser and it is reasonably successful but the sandbox makes it specifically unsuitable / high friction for doing things that need local access to files, network, etc. And it is ridiculously high overhead if you just want to run something simple. Then remote access is even more a debacle. Can I access an application running on my windows host from my Mac? can I forward that through a tunneled connection?

TUI is a simple, universal protocol that does what you need and is natively remote. Whatever I use locally will seamlessly work over an SSH connection.

And it's a big middle finger to the OS vendors who thought locking everyone in by making everything incompatible or ecosystem specific was a winning strategy.