The joke meme showing Batman is all nine alignments really underscores how poor a fit that is. In comparison, I suspect getting the Nature/Demeanor right for him would generate far fewer than nine serious entries and be a good example of how one's Demeanor can be wildly different than their inner nature.
The alignment system is certainly an idiosyncratic way of conceptualizing people and the world. It works both wonderfully and terribly.
Going back to 1978, I suppose the ninefold alignment system was a relative step forward in character creation and role-playing. Likewise, Nature & Demeanor was another step forward in 1991. And in a game full of scheming and deceit, wearing masks and exploring what being undead is like, it was perfect.