It is something Lord of the Rings and by extension d&d absolutely fails at-- the simple idea that you have a whole damn population of people and thus you have the depth and diversity of a whole population. And maybe there are reasons to come into conflict with them that can be hardly resolved without violence. Yet, at the same time, maybe there are aspects of them to admire and respect. The "other" isn't necessarily simply comprised of the worst of your own culture.
All human conflicts throughout history had this complication. Why can't a fictional scenario in a fantasy world carry the same?