I've installed cinnamon instead of gnome and upon depclean, notice, that xorg is to be removed. Shouldn't gnome-extra/cinnamon depend on xorg? Or am I misunderstanding something?
This doesn't really seem in line with other desktop environment packages. I don't see (direct) xorg-server/xorg-x11 dependencies in KDE, XFCE, MATE, even GNOME.
Some desktop managers (GDM, sddm) do seem to depend on xorg-server, but not every manager does (lightdm, lxdm, xdm), and Cinnamon doesn't provide/declare a manager. So IMHO that's up to users to install and set things up the way they want.