https://linux.kde.org/#what-kind-of-base-technology-does-kde-linux-use
They disagree with calling it arch based:
What kind of base technology does KDE Linux use?
KDE Linux is an “immutable base OS” Linux distro created using Arch Linux packages, but it should not be considered an “Arch-based distro”; Arch is simply a means to an end, and KDE Linux doesn’t even ship with the pacman package manager.
KDE Linux leans on Systemd for a great deal of functionality. Updates are atomic and image-based, with the last 5 OS images cached on disk. Only the Wayland session is supported. Apps primarily come from Flatpak.
Learn more about KDE Linux’s architecture.




Absolutely, it looks like it’s mostly managing expectations that come with calling something arch based.
In your recipe analogy, calling your new cookie recipe, which you based on your granny’s chocolate chip cookie recipe, “chocolate chip cookie based”, but ending up with a raisin cookie (you removed the chocolate chips) would be false advertising, even if technically true in the way you describe.