I really struggle to believe that remote desktop is expensive to implement/run. And no, this isn't an improvement: It used to be that everyone used Xorg, so all desktops had largely the same features. There was, for example, a way to set keyboard layout that always worked (setxkbmap), and it always worked. Now there are endless different compositors, and they all have different features. Do you want to try a new option? Good luck finding out if it actually does everything you need! Do you need a particular feature? Well, I sure hope you like one of the specific desktops that supports it, because it's a toss-up which support what.

Actually it is a massive improvement: expensive niche features are now optional, features you have to discover and handle dynamically. This helps to avoid developer/vendor lock-in by 'tons of features required'.

If I am not too mistaken there are several "remote desktop network protocols", maybe the dev teams behind them could agree on a common network protocol.

And the more compositor implementations, the merrier, a bit like the x11 window managers.

I am coding mine for linux and AMD GPUs, as a hobby, in RISC-V assembly running on x86_64 via an interpreter (thanks to wayland being an IPC interface)... well until very recently, it has been more some kind of research and development of a "method" to code modular assembly projects with a minimal SDK, in other words to decide on various technical compromises requiring coding _real life_ software in order to hit the right sweet spot.