In the same way that we had to get used to Cocoa and Node.js. They both take a back seat for many people (I have written ~2 lines of code for each).
Wayland - Is still Linux specific. BSD might go that way but I doubt macOS, Windows, AIX or Solaris will follow (mostly due to lack of interest). Its just yet another backend for SDL/GTK to deal with; not the vast majority of developers or users. (other than perhaps seeing lots of our favorite software die as part of the migration).
Rust - Is more a dependency manager than an actual language. It will always rely on C (and to a lesser extent C++) for the actual system-level implementation, just like Python, Perl and Node.js do.
So frankly, I think we are already as "used" to them as we need to get.