It’s very nice to not have a dozen different versions of the same distro to parse through and figure out that are simply the same distro with a different DE. Moreover, very few of them offer this many options.
Cachy could be doing a better job explaining what the user is looking at here and who each of these is for. Pretty easy to sum up in 1-2 sentences…
Maintenance. Your distro has to support all the provided desktops, which includes a multitude of display managers (“login mask”) doing their own opiniated session thing.
For example, Gnome is no longer supported by Artix, because they have now a hard requirement on Systemd.