Within the last 10 years and the next 5 years, software using old hacks instead of GUI toolkits are expected to switch, yes.
People can choose to continue to use X11 until KDE Plasma 6 hits Debian stable.
I don’t see a problem. Nobody forces Wayland onto anyone yet, except for bleeding edge distributions like Fedora. And unless you’ve been severely misled, you should know what you signed up for when you installed Fedora.