TBH I can see both sides of the argument so I’m not particularly mad at anyone here.
Running rootless X might be unconventional, but they do have a point that without pushing the changes, they’ll never get adopted. And that’s not just limited to software. And their security argument might not be relevant now, but we also once thought Intel CPUs were safe, and see where we stand now. We also once thought OpenSSL was rather save until Heartbleed happened. So just because now there are no (known) attacks on X, doesn’t mean we can extrapolate that on the future. So I can totally see why they are doing this especially with respects to RHEL where security is arguably a selling point.
The argument of “it’s nvidias fault” might have been a bit too fast (though we also don’t know if those answers were from actual Fedora devs or from random people that just threw something at the wall). But on the other hand they do have a point in saying that if their drivers were open source, people could fix it themselves. For how it is now we will always have to wait on nvidia for no particularly good reason. See also: AMDGPU.
From what I know (and I don’t know if this is still up to date), nvidia also just straight up doesn’t support Wayland either… like… at all. Think about Wayland what you will, but eventually it will probably replace X at least on the Desktop side of things.
So all in all, I don’t think that change was with bad intention, and nvidia may or may not be at least partially to blame.