The point is that the X Server is an ancient mess of code held together by duct tape, with countless deprecated APIs. Most login managers don't even let you run it rootless, which means the vast majority of desktop users have all this running as root, and rootless X wasn't even possible until very recently... and was motivated by Wayland anyways.
So the point of Wayland is to have a clean and simple foundation, with no obvious security vulnerabilities, no overhead, and no kludgey workarounds or ancient APIs.
So the point of Wayland is to have a clean and simple foundation, with no obvious security vulnerabilities, no overhead, and no kludgey workarounds or ancient APIs.