Nit: RDP’s roots are more in multi-user windows like Citrix Metaframe than in remote administration. I’ve found it to perform better than the alternatives (remote X11, VNC, Chrome Remote Desktop) for remote GUIs. Nomachine is the only alternative that was close to its performance.
(And before somebody jumps in to correct me - in ancient times X11 performed quite well over the network but modern Linux GUI apps are no longer designed to minimise X11 network traffic)
Things made for game streaming will be more responsive at the tradeoff of massive bandwidth usage in comparison. RDP can work over slow connections reasonably well.
Massive bandwidth usage and video compression artifacts. It's fine for games and media consumption, but may be problematic for office work.
Remote desktop protocols prefer lossless compression to achieve pixel-perfect rendering, at the expense of framerate/latency.
RDP is unique in that it's not just streaming, but integrates with Windows' GUI stack to actually offload compositing to the client. This however works less and less well with web and Electron apps which do not use native OS widgets.
Agreed that RDP is very well designed. And we don't have an equivalent in Linux or Mac world. All competing protocols are a compromise. I am particularly impressed with good multi-monitor support in RDP. Competitions has had more than a decade to get it right. But I am unaware of any that does.
If I connect remotely from a 2 monitor setup, disconnect and re-connect from my laptop with just a single display, it all magically works. Everything readjusts automatically. I don't know of any other remote desktop protocol/tool that does this so well.
(And before somebody jumps in to correct me - in ancient times X11 performed quite well over the network but modern Linux GUI apps are no longer designed to minimise X11 network traffic)