What does evil even mean? Evil as defined by whom, because of what exactly? Good and evil are in reality subjective terms, and they have meant a whole lot of different things throughout history. It used to be that simply not worshipping the right god in the right way was a sign of blasphemy and thus evil. It still is like that in some parts of the world. Apostasy is punishable by death here and there.
If we're going to get this "real" in a gaming board discussion then we should probably not complete skate over what "evil" actually means. But this is usually done for expediency in any gaming context, because good just is, and so is evil. And that's okay, because playing a game usually means trying to work our way through a story rather than getting into the nitty-gritty of philosophy.
If we can arbitrarily define that all demons are just evil, whatever that word means, and a bunch of deities are simply good, whatever good means, then it hardly seems appropriate to get completely bent out of shape that, say, orcs are considered evil at a racial level. Whatever evil happens to arbitrarily have been defined to mean in that context, obviously.
To clarify, I do not mind drow or greenies or other races, humanoid or non-humanoid, getting fleshed out more. But the assertion that no single intelligent race can ever be described as "evil" from the perspective of the arbitrarily defined "goodly" races strikes me as forcibly anthropologizing the entire setting. And that's too much. We are not the only creature in the world, not are we so interesting that absolutely every story ever should only involve humans in every single role, even for the non-humans. It is okay for other beings to be something other than human and one would not expect non-humans to necessarily think, feel, or behave in ways that we humans would consider "good". Whatever that may be.
Short version, by all means do nuance the drow more, but please don't let it get to the point where butchering orcs is "evil" and only asking them over for a nice cup of tea and biscuits is "good". If I wanted that much social realism, I wouldn't be playing a fantasy RPG.
