Wayland is all about protocols being implemented by the DEs. So far there is (afaik) not a fitting protocol for remote desktop usecases.
Even screensharing is still a PITA, since the desktop portals work independantly from the requesting application. App asks portal “what apps and screens are there?”, then the user gets prompted by the portal to select the allowed entities. Then the application lists these again, user picks it again, and then gets prompted by the portal again to basically confirm that you really want to share it. That’s mostly a discrepency between how the apps work (on X11, Windows and OSX vs Wayland). But it’s in the end still a pain for the user.
Grabbing and manipulating inputs is another matter. Allowing that globally is a security issue, so Wayland doesn’t do it. But remote desktop needs that. So now there needs to be a standard protocol that the DEs implement to allow remote desktop solutions to access inputs. Or they do it like RustDesk, run as root and intercept inputs before wayland gets a chance to intervene.