"No thanks, I've already played Assassins Creed: Black Flag like 10 years ago"

I've already scrapped the whole thing already anyway. It's an interesting concept, but it just didn't work for me. It makes sense if I was distributing a specific build to loads of machines, but for my own PC, its completely overkill.

If you’re rebasing on new commits then you set it up wrong. Consult the new instructions, there a lot more clear.

I had to rebase at the time because they completely reworked the bling stuff and scrapped Yafti, so my previously working builds were failing from that point onward, and I just thought it better to return to Arch.

This is just the Universal Blue template, but split out into it's own thing, right?

I was messing around with my own Fedora Silverblue build based on the older template, but it was a lot more annoying messing with the build pipeline and having to rebase onto new commits and stuff than it was to just set up everything I wanted in Arch and call it a day.

Someone smarter than me can probably explain this way better...

As far as Wayland goes, If I remember correctly, it's mainly just a protocol, and Gnome/KDE do all the actual work of making stuff happen, so both need to support it to have it work correctly. Like if Wayland was a language like French, Gnome and KDE need to know the French words for something before they can have conversations about it, and Gnome hasn't been as studious with it's dictionary in regards to VRR. X11 just has an ancient code-base, and adding support for anything involves a lot of effort to make sure something else isn't broken by the addition.

Gnome hasn't officially merged support for VRR yet, but there is a merge request to add support, and a patched version built on that code available if you want to try it (mutter-vrr, gnome-control-center-vrr) at least on Arch Linux's AUR.