I don’t think a good response to " breaks " is to say "yes, because was designed to work with and hasn’t been updated to use ". Part of the task of replacing something old - onerous though it be - is to provide a smooth route to support old programs and functionality.
Wayland deliberately broke everything, but then was rolled out prematurely at least on some distros, before giving the vast X ecosystem enough time (which was guaranteed to be a long time, due to how large and entrenched it was) to update. Besides which, the “OUTDATED” post has an awful lot of things you acknowledge are still issues!