I wonder how many people are using KDE or Gnome these days. I'm pretty sure I'm using something other than KDE and Gnome on my Linux installs.
Just over half of those participating have installed Gnome/KDE/Cinnamon
https://qa.debian.org/popcon-graph.php?packages=gnome-shell%...
And it looks as if about a quarter totally are using Gnome/KDE/Cinnamon regularity (rest could be switched off of course!)
https://qa.debian.org/popcon-graph.php?packages=gnome-shell%...
Popcon statistics are notoriously hard to interpret though so a large pinch of salt needed.