Not a problem for obviously-correct changes of a couple of lines, but most PRs aren't like that.
Open source developers are not required to spend their time prioritizing your priorities. You just have to look to Xlibre to see that a lot of contributions are quite bad quality, and in a C codebase of Xorg's complexity and security profile it's not a small job to review things.
As it is, the community got constantly browbeat with 'this is the future' and 'it's so much faster!' when recent benchmarks have proven that to be false.
You'll probably find it to be a not great experience, since almost all the people who spend their time actually working on graphics and GUIs in the Linux world prefer to work on Wayland. So X doesn't get much love these days (and you're not entitled to their efforts after all). But it's not like they erased all the old X code from existence.
I'm confused where I'm likely to be suffering. If I start using Wayland tomorrow would I even notice? Apart from having to switch DEs, of course.
You may notice issues with some GPU drivers if you have hardware with new drivers, because older GPU drivers contain X-specific workarounds which new drivers may lack (I know this is an issue with the Apple M1 GPU, I suspect it might be an issue with Panthor as well). But that's not really relevant with typical consumer hardware.
Desktop environments have varying levels of X support these days. GNOME hasn't been adding new features to X for a while, and GNOME 50 completely drops X. So if you're a GNOME fan you may not like that. KDE ends X11 support in 6.8. But it's always possible to stay on GNOME 49 or KDE Plasma 6.7 forever, or use an X11 window manager.
The X11 back-end is deprecated in GTK 4, so don't expect a ton of improvements to it, but it'll remain supported for all of GTK 4's life so you probably won't notice anything there immediately. But it means GTK 5 will drop the X11 back-end entirely, so at some point in the coming decade, GTK applications will gradually stop working.
Regardless of GUI toolkit, applications are slowly moving towards the XDG Portal way of doing things instead of the X11 way; which is fine, there's no reason why X systems can't support the portal dbus APIs, but I suspect that there will be more issues there once applications start dropping their X11 implementations of things. This is an area under active development and I would expect X11 to not see much of that development. I have no idea if anyone has implemented a portal for X11. Maybe you'd have to do that yourself eventually to keep new versions of certain programs running, I don't know how the state of portals is on X.
There are other things too that software can do to break X11 support even when their toolkit supports X, and expect that this has started happening to some degree and will slowly continue.
Hopefully someone will come up with Wayland emulation layer for x11 then.