I think defining and elaborating on, say, goblin cultures and their worldviews would be welcome in the contemporary game, but it stands in stark contrast to the position that they need to be different (i.e. inherently evil) to serve as fodder for the PC combat machine. Is the point of elaborating difference for the sake of creating vivid and deep alternatives to the human societies in a given setting, or is it just to provide monsters for the pcs to kill?
Also,
@Crimson Longinus, you mentioned Klingons in the other thread, but I don't get how that's not the 'humans but in rubber masks' situation. Klingons are represented as having a particular culture, but that culture is basically comprehensible by the human characters as it is just an exaggeration of certain features of human culture. Unlike the Q or the Borg that are more truly alien.