Geeky Linux forums tend to be people who haven't given new distros a chance in decades, and still think Gentoo and RedHat are the major players. (Desktop Linux it's Ubuntu, followed by Debian and CentOS).
I know you mentioned desktop in the end but it’s funny you got this exactly backwards- almost every Linux on a computer is either gentoo (chromebooks) or red hat/clone of red hat (servers)
Debian family is actually much bigger for servers in most of Europe. RedHat seems to be more of an American thing (of course you'll also find redhat in eu and debian in usa, but as a general rule)
These rankings are based on page views and are easily manipulated. Imagine how many people click on one of the top 20 distros they aren't familiar with to see what it is, which just cements its spot that high up.
The most interesting section on distrowatch for me is the top reviewed distros.[0] It shows what the hard-core Linux users are (at least) appreciating, if not using.
N.B. It has nothing to do with popularity (number of users)
