No, sorry. X11 clients are eternal, there's just way too many of them out there that are line-of-business and will never be ported to anything else. So I'm always going to need some solution to make those apps work, and since for the foreseeable future that probably means "run a nested X server that translates things to the native display server's API", that means Xwayland isn't going away any time soon, and if/when it does it'll be replaced by some other translation layer I'll need to support.