Except when X doesn't fucking work ™ and hasn't properly worked in literal decades. I don't think I've ever managed to get rid of horizontal tearing with X. Calling X feature complete is pretty funny, but it isn't. So many things were never fully implemented, because it's just an impossible amount of work or would require some major rearchitecting. You don't have to deal with updates because literally no one wants to develop it any further or even maintain it. The devs have moved on to Wayland or other things.
It's fine if it works for you, but I'm getting tired of Linux conservatives projecting their own experiences on everyone else and declaring Wayland as "not ready yet" and handwaving all of X's obvious problems away because they're used to dealing with them. I've used Wayland as a default for all my machines for years. After a rough beginning where major features were still in development, now it works. XWayland works. Native Wayland apps work. I don't have tearing anymore. I'm not going to pretend that that's the universal experience, but a lot of people are using it just fine right now.
Ymmv with Nvidia, but that has nothing to do with development focus and everything to do with Nvidia's refusal to use the same interfaces Intel and AMD use. Most of the way Nvidia works or doesn't work with X or Wayland is down to Nvidia's driver stack. Personally I've not had much positive experiences with Nvidia on X.
That happened literal years ago. The reason you're only noticing now, might be because KDE has gotten their Wayland implementation to a reasonably stable point. Gnome has supported Wayland for some time now and other DEs probably don't have the resources to move on from X. I don't see the distros that are only switching over now as major contributors to any development specific to Wayland.
I don't take issue with your preferences. Maybe you're better off with X for now, that's fine, but you make it sound like Wayland is just full of issues and has barely even entered some kind of pre-release state for software masochists.