IIUC, RDP (Microsoft's remote desktop protocol) sends draw commands across. It's the default way to access remote desktops on Windows. Conversely, AFAICT, the default way on MacOS and Linux is VNC which IIUC sends all the pixels (with compression). I've noticed for years I can work remotely, edit code, etc on RDP. I've done it around the across 8000 miles and had hardly any lag. Conversely I'm trying to share 2 computers right next to each other in the same network via VNC and it's horribly laggy.
Is this just not an itch anyone has wanted to scratch in the last 25 years? On Linux you can maybe XWindows your way to a faster connection by what about Mac? Also, RDP seems to let me run GPU based stuff where as XWindows you're actually not seeing the computer's display.
1. There is some trade off of latency for bandwidth: it may take more time to figure out a small change to send over the network. Looking at api use from eg X may help with old apps that make small updates but more modern apps (or even modern fonts) which just render to gpu buffers and composite are less amenable to this. Very modern apps that use special apis to do lower latency scrolling/resize may be a little better.
3. A lot of the time for Linux the solution is to use ssh and terminal apps as they tend to make smaller updates and require less bandwidth. You can also try mosh to compensate for high latency connections. Text editors can work ok in terminals, especially fancy modern ones with eg mouse support. And for web things you can do set up a socks proxy over ssh which I think can work for a lot of apps which are really just web sites. So this may be part of the reason: fewer people see Remote Desktop as necessary.
4. I’ve had reasonable success with xrdp on the server and a windows client. One needed to select 32-but colour to get a better protocol version and turning off double-buffering in some apps (eg emacs) helped. But that was over a wired high bandwidth low latency connection.