I've been using the Kubuntu 26.04 prereleases for a few weeks. No surprises from KDE, but Wayland has broken a few things. Autotype in Keepass does not work, keynav and even the Wayland keynav forks don't work, and Wayland does not support priority keyboard layouts for switching between two specific layouts.
I still mostly use Xorg though, I only have wayland on a tablet.
https://en.wikipedia.org/wiki/KDE_Plasma
https://kde.org/plasma-desktop/
Is this, like, a “GNU/Linux controversy” thing?
It's really only calling it "KDE" in isolation that is a bit off. On the GNOME side, such a reference makes sense because the desktop environment is named GNOME and it's run by the GNOME Project/GNOME Foundation. I.e. a bit reversed which word in the order refers to the org's vs DE's name.
Most of the time people will probably figure it out at the end of the day via context either way though.