UPDATE: Long story short…I still have no clue. Unplugging my second monitor got the proprietary drivers working properly on KDE Neon, but not on any Arch based distro I tried. I tried kernels from 6.1 to 6.18, and drivers all the way from 470 (disaster) to 595, dkms and open. Followed all the advice on the Arch docs regarding power management, blacklisting, etc…
Soooo…I don’t know. But I’m up and running with a single monitor on an Ubuntu based distro, which isn’t ideal, but right now I’ll take what I can get.
hmm well i never had this specific issue and im not an expert in driver issue.
SO TL;DR I cant help you. sorry.
BUT (AND I KNOW IT SOUNDS DUMB or you might be doing it already)
I would recommend you do some A/B testing.
keep your setup the same and change only one thing at a time (like driver version, Wayland vs X11, kernel options, or compositor) so you can pinpoint exactly which change is causing the problem.
Maybe take a look into nvidia-{open,dkms,beta, etc} packages.
or something else entirely.
This might help you to at least get your system going so you can do your Video editing, graphic design, 3d modelling etc. If u want to get your system up and going right now(deadlines or something else) its not a bad idea to temporarily install windows and attack this problem later in free time with no pressure.
I hope you find a solution to the problem.
Worst case scenario is I end up reinstalling the X Display server for now. No real time constraint. Just annoying.