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.
EDIT: Nvidia dev posted that support is planned in the 555 driver, with beta release planned for May 15: https://github.com/NVIDIA/egl-wayland/pull/104#issuecomment-2010292221
https://invent.kde.org/plasma/kwin/-/merge_requests/4693
there’s already a non-draft implementation, if I had to guess a few weeks before it’s merged, and then you have to wait for a release, and then your distro has to package it. So, it’s gonna be a while.
BUT, I think much more importantly is when it is merged into xwayland
https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/967
Which should be fairly soon!