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.
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.