RDP is far, far more advanced than X11. In addition to doing "GDI over the wire" much like X11's draw calls, RDP supports compressed bitmaps and streaming video, remote audio, remote file system, remote USB, clipboard sharing, and more recently remote GPU. (Yes, I know about GLX, it's incredibly old and hasn't been updated.)
RDP is to X as PowerShell is to bash: better than the Unix standard thing because it isn't weighed down by Unix community baggage.
RDP is to X as PowerShell is to bash: better than the Unix standard thing because it isn't weighed down by Unix community baggage.