I feel like I should offer a small correction: Slackware does not ship with (as listed) “GNOME, Cinnamon, MATE, Budgie, LXQt, i3wm, Sway, Hyprland, Openbox, COSMIC, Deepin, awesome, Qtile, Pantheon”. While these can be installed manually, of the options listed Slackware only ships Xfce and KDE; it also ships WindowMaker (nearly featureful enough to qualify as a DE on its own!) as well as Fluxbox, Blackbox, and FVWM2.