Last I heard, Nvidia was planning to release support in their drivers for explicit sync in Wayland in May in their 555 beta driver release actually it looks like it might not be merged until Nvidia’s 560 driver. I wouldn’t expect full support until at least then. Maybe we’ll have some support in Fedora by June? You’ll hear about it in the Linux and Linux Gaming communities on Lemmy, so look for it there. Fedora will be pretty early adopters, so it shouldn’t be long after the changes are merged until you’ll see support in Fedora. Do note that it isn’t as bleeding edge as Arch though, so expect it to lag a week behind Arch support (maybe a little more?).

Also, if you’re between KDE and COSMIC, go with KDE. COSMIC isn’t even in alpha yet, and there are no distros that support it yet. KDE has great support and just merged a lot of performance and bug fixes in the last mega release (Plasma 6). Fedora has a KDE spin, and Plasma 6 will come with Fedora 40’s KDE spin when it releases on the 16th of this month. That will be before explicit sync support though, so I’d say there’s no rush unless you’re really interested in Linux. Nvidia on Wayland is still pretty good without explicit sync support, but explicit sync is essentially the last thing that most people are waiting on. It’s kind of like the last nail in X’s coffin before Wayland is 100% viable on Nvidia. It will fix a lot of little annoyances (flickering, stuttering, etc). KDE has VRR support and a lot of great gaming support, so it’s a good choice.