This isn't the appropriate comparison. What they said is "x86-64 is incredibly slow", and then when you teased them for details, what they meant was "this Linux feature is incredibly slow on x86-64". To which the answer isn't "it's fast on RISC-V", but rather, "that's a problem with Linux, not x86-64".
If you have a beef with GNOME, then bring it to GNOME. Don't pin it on a tangentally related technology which bears none of the fault, and which has had hundreds of thousands of hours of work invested in it by volunteers all to make something nice for you to use.
It's not an end user's job to tease apart what specific thing is the root cause. If something changes, and their system feels slower, they're going to reasonably assume the thing that changed is at fault. That's doubly true if there's an easy switch to turn that thing on and off (which there often is, by picking a Wayland or non-Wayland session at login), and they can easily evaluate the difference in isolation. It might be cathartic to spend time yelling at people about who is actually at fault, but fixing the root cause would make there not be a fault to seek blame for.
People aren't going to stop running GNOME en-masse. Distributions are not going to abruptly abandon GNOME. If (and I do mean "if") there's some issue with GNOME's Wayland implementation, that's going to be many people's primary exposure to Wayland as a technology.
People will continue working on optimizations, to many places in the stack. It doesn't matter where the fault lies or where the fixes need to happen, the net result is people saying things like "I switched to Wayland and things got slower / less smooth / etc", and they're going to continue saying things like that. It'd be nice if people phrased it more that way (slowness associated with switching to Wayland, rather than Wayland being slow), and provided more details about their environment, rather than implying that "Wayland" is a single piece of software which should incur their ire. It'd be even nicer if there were less ire to go around because more things Just Work.
It's also entirely possible that some of the people in these various threads have issues with some other piece of software in the stack.
> If you have a beef with GNOME, then bring it to GNOME.
I'm not the one with a beef with GNOME; you seem to be. If you have a problem with GNOME, take it to GNOME. GNOME works great for me, and I don't care which Wayland protocols it does or doesn't choose to implement. You haven't even specified what precise change you think ought to happen there, just some general complaints about protocol extensions.
If you want this to stop, make GNOME's performance better in the ways you envision, because it is the experience most Linux users get. (Quite a lot of work has been going into GNOME Wayland performance lately.) Arguments about Wayland protocol feature politics don't necessarily make the out-of-the-box experience worse; for many people it's a good "Just Works" experience. Stop telling people they need to switch desktop environments to get a better experience; some fraction of people will go "if I have to switch, I'll switch back to Windows/macOS/etc". A vanishingly small fraction of people will go "oh, sure, I should switch to a different window manager and environment that isn't what I'm used to and doesn't necessarily have the integration I'm used to, and switch my apps to match too; this makes me happy", and those people know who they are already.