Since nvidia drivers do not properly implement implicit sync, this protocol not existing is the root cause of flickering with nvidia graphics on Wayland. This MR being merged means that Wayland might finally be usable with nvidia graphics with the next driver release.
I only have experience with my current GPU (3070 ti) and only in Hyprland, but the only flickering I have is in steam windows, everything else works flawlessly on 535 driver. Still excited that it may be fixed soon!