This depends: Do you care about details, or not? If not, a hand wave in the direction of "everything's the same" will suffice and the discussion's over. OTOH,

This depends: Do you care about details, or not? If not, a hand wave in the direction of "everything's the same" will suffice and the discussion's over. OTOH, if you think there are good, detailed reasons why XFCE is not KDE is not Gnome is not LXDE, then you can probably see why standards are helpful, insofar as they can be designed to be reachable without compromising unique leverage points.