Hello, you've already probably tried this but just plugging in.
Have you tried changing HDMI / DP cables / ports? Is it possible you're running your screen from your motherboard instead of your graphics card?
If not the case, have you tried swapping from graphics card to your motherboard HDMI output whenever you get the black screen? Might be a case of Linux using the wrong graphics output...
Good luck on your endeavour!
Half of what you said are either issues with your current compositor's implementation or Nvidia driver related issues, since Wayland on both KWin and Mutter under AMD don't present any of these issues, atleast for me, while I had the latency issue you mention with my older 3080 card.
The protocol is still under development after 25 years yes, but at the end of the day you vote with your wallet, and Nvidia clearly doesn't give a shit about open-source or Linux as a whole since we're a minority.
It's "hard" to us because we actually uncheck the telemetry settings and care about not having a Microsoft account on, including the additional debloating afterwards. For the average user, clicking next every step, ignoring the data harvesting effort and creating / using a Microsoft account is part of the experience and "normal" to them.
Having swapped to Linux on Pop OS and later onto Nobara recently, I strongly disagree.
As my personal experience on 525, 535 and even beta 545 with a 3080, so much as swapping onto a Wayland session implied lag, screen tearing issues, and stability issues / crashes on KDE and GNOME, to the point that I ended up selling the 3080 for a 7900 XTX because of how everyone said the AMD experience is so much better and it is.
True that I havent tested it on a laptop so maybe Optimus support from Nvidia or the latest drivers have added stability overall, but this was definitely a problem in desktop for the last months to me.
Done, love KDE, I hope 6 kicks ass too!
I mean, they will when those same powertripping mods begin banning over petty things. That's how you get people to move from subreddits / Reddit.
The mother of all bottlenecks.