And D&D can define that however it wants. Notably, Malazan was the author's D&D campaign before it was a series of books, so the notion that what's going on there is inappropriate for the game is just historically ignorant. D&D has always been influenced by the rest of the fantasy genre. It picks and chooses what things influence it, and how those influences are expressed, but the idea that D&D stands alone has never been accurate (nor should it be).