Mercurius
Legend
One of the problems with this, when compared to the real world, is that a vast majority of "evil" done by humans in war and expansionism is done in the name of religion. And while we could argue for the rest of our lives whether any of Earth's deities are real or not, in most fantasy settings they are very real to the PCs and NPCs. So if your god tells you to go and conquer your neighbor, you do it. And if you worship one of the darker deities that is morally grey or outright evil, you use all the horrible tools you can in your conquest. This is also why I do not participate in games where evil alignments are allowed. I don't want to be associated with any of that, even in an imaginary way.
I hear you, and it is a good point. D&D--as a domain of fantasy and imagination--cannot, and generally does not, represent actual reality, in a similar way that a piece of art--unless it is photo-realistic (which I'm not a fan of)--doesn't accurately or exactly portray what it is representing. D&D, as I see it, is mythic: it deals in archetypes and ideas, not literal realities.
This, I think, is where a lot of the current concerns stem from, a perspective that art (D&D) must accurately represent life (real world ideas). Now D&D can be played that way, but that isn't the traditional default approach. There is a reason we like to play make-believe, so that we can explore other worlds.
I mean, who wants to play a D&D game where you have to wait in line at the fantasy version of the DMV? Or stuck in traffic? Paying taxes? Dealing with gout?

As far as evil is concerned, I think where we both agree is that neither of us wants to inhabit the imaginative space of being evil, at least for too long. It is interesting to consider, and when I DM of course that is part of it, but a DM has greater distance between themselves and the monsters than a player and their character, if only because a DM takes on the roles of multiple creatures and people, all over the spectrum.