You basically just described Google's Flutter framework. It's currently only mobile but I see it moving into this space at some point - or already is I guess if you count Fuschia.
You can get it working on Desktop (I've got it on Windows with the help of https://github.com/ds84182/flutter_sdl and few other hacks, but certain things are missing - there is no support for mousewheel events, docking, or more than one window. Or keyboard input (though that should be easier to add than the three listed).
At least when concerning all major GUI libs.
It's more like a markup driving an immediate-mode graphics API.