GNOME 3.34 Now Supports Starting XWayland On-Demand
This work allows for GNOME Shell to be started without requiring XWayland for initialization and to only start-up the XWayland server when there are clients looking to actually use it.
While as great as it sounds (and it is, it's been a long time coming), it's not being enabled by default at the moment but hidden behind a GSettings key. There are some race conditions, an issue with PulseAudio accidentally starting up XWayland, and some other quirks to work out but for GNOME 3.34 it's at least ready as an experimental feature. That knob is the autostart-xwayland setting.
The code was merged last night for those interested in XWayland on-demand under GNOME.