It’s for Linux too. Otherwise VRR (gsync and freesync) can’t work. But the compositor needs to support this. In KDE, this checkbox needs to be enabled in the compositor config:
However, I believe this is only for X11 and with Wayland there’s no way to disable compositing. Not sure if it’s even needed there. With X11, compositing adds some input lag and also you can get some stutters (skipped frames.) Wayland might not have that problem.
Also, there’s also a keyboard shortcut to toggle compositing on/off in KDE. Alt+Shift+F12. So even with that option disabled, you can manually disable and re-enable compositing whenever you want.