In all serious, while I use XFCE on most personal things, if I was pressed to choose between the big two, I think I'd choose KDE over GNOME; in fact, when I had to loan my younger sibling a laptop recently and that laptop was too old to run Windows 11, I put them on Debian with KDE. I think KDE is also my backup plan if major applications start dropping xorg support before XFCE has implemented sufficient Wayland support, although they seem to be making progress.

Out of the box, KDE tends to be more Windows-like and just better for my workflow in general, while GNOME can just be... weird. Like, I don't quite hate GNOME as much as I used to - I plan on throwing it on an old Surface tablet soon - but like others have said, it's very opinionated and doesn't like customization and whatnot. I also resent GNOME in the sense that they tend to make design designs (such as in GTK 4) that reduce ease of interoperability across different open source desktops.