No, it’s not! 
That’s a rumour that is completely untrue. At the very least, Xeyes will live for as long as I live. If Arch drops X support (which is unlikely), I’ll use Debian, if I have to.
Yeah, Plasma is flirting too much with Wayland. I hate that crap, it’s not finished (it looks like it will never be finished) and it’s not ready for my typical use cases. Now, Plasma 6 will still have X support, but they plan to drop it in about a year or so. A long time before that happens, I need to find a suitable alternative. It will probably be a very custom build of dwm or LXQt. I’m already phasing out Kate, in favour of Emacs. For now, I will continue to use Konsole, as there is really no alternative to that that I can think of.