I am not sure it’s truly fixed.
As the monitor always stays with GSync ON in KDE6, even if you disable VRR in the UI and through environment variables.
There might be other underlying issues possibly related to sync to vblank, on the gpu driver side.
There are more discussions of the problem in the urls below that needs fixing.
This should have ULMB2 turned on, but for whatever reason, be sync to vblank / vsync or some other issue being enforced, gsync are kept on.
Where, in X11, ULMB2 are turned on, in place of Gsync.
Here is another issue on Wayland, possibly related GPU utilization always near 70% on Wayland when gaming - #2 by random-user00 X11 has the right GPU usage, while Wayland are most of the time lower, at least in DX11 games. In my experience, DX12 (VKD3D) has better usage, but still not as responsive or fully use.