A big improvement has been merged into XWayland called DRM (Direct Rendering Manager) Leasing, which should allow good VR support under Wayland. Something we've been waiting on!
From the commit message:
This commit allows X11 clients running through Xwayland to lease non-desktop connectors from the Wayland compositor by implementing support for drm-lease-v1. In order to not deadlock with the Wayland compositor if its response to a lease request is delayed, the new interface in _rrScrPriv introduced in the last commit is used, which makes it possible to block the X11 client while a response is pending. Leasing normal outputs is not yet supported, all connectors offered for lease will be advertised as non-desktop.
Want to learn more about it? Developer Drew DeVault wrote about a bunch of the work involved and some explainers back in 2019. The gist of it is that this was all needed for the hand-off between your PC and the VR headset, so you can actually get everything to display correctly.
Thanks to this work being hooked up, it means VR games that don't support Wayland directly that need to be run through X11/XWayland should hopefully work well. Support should land in XWayland version 22 sometime next year. Just another tick in the box towards Linux distributions and Linux gaming going all-in with Wayland.