Ready means if everything is flawless to MacOS/Windows levels, where you never have to think about display server compatibility, and that's where X11 is still king despite the performance shortcomings. At least it always just works™ and compatibility beats performance most of the days.
I could excuse it if it had been 4 years old or so, but it's old enough already it can drink and smoke in Europe.
If that game were to be launched today and feature a setting in the same time delta, it would be set in 2008 when movies like The Dark Knight or the first Iron Man launched.
How time flies.
Xorg was a fork of XFree86, which was released in 1991. So that codebase was 17 years old when Wayland was first released. I don't think the date of the fork is what's relevant here.
I could also argue that you should be comparing the Wayland protocol (2008) vs the X11 protocol (1987), or even older versions of X (1984).
I think is more probable that anyone will have a problem in Wayland than X