Replacing good legacy will always be a struggle. X11 works pretty well and has been stable for decades. Most of the things that suck about it already have workarounds.
The advantages of Wayland are not directly visible for the end user. The security part will be great once it’s completely integrated on the distributions to give granular permissions to software. The simpler apis and greater performance will help libraries creators, but most developers don’t touch X directly and won’t touch Wayland either.
Being stable for a couple of months is not good enough. People will use it once distros trust it enough to make it default, and this will probably only happen once Wayland or its compatibility tools work with most software and major applications work significantly better on it.