At which point, inevitably, a new generation of devs will look at the now-huge wayland codebase and say "what is all this cruft?! who wants color management in what should just be a display protocol? let's start over and This Time We'll Get It Right™", and the circle of life will continue.
Luckily they’re both WIP at this time. That said, the color management, just the spec, has been in the works for what feels like ever—to the point that some of the window managers are going around them in implement their own spec.
Actually, I would expect that it will be a separate protocol, so the next generation will instead ask why you would ever leave color management out of the core protocol and proceed to immediately bake it in.