All that said, some good points here and some people who just wanted to argue about the alignment system and not the actual point put forward with the OP. Thanks for your time tonight.
The alignment system doesn't care what the individual considers themselves or really too much about their motives, just their actions. Ravenloft did a good job of illustrating this. Several Darklords view themselves as justified or even virtuous. All are Evil in the statline.
Medium Rare with a good sear. The thickness of the cut may affect this and make me have to select Medium, so as not to get a steak thats too rare in the very middle.
Sorry. This is topic drift. I'm not arguing over if the system has merit. That's an individual opinion of what works for the games you want to run or play in. I am saying that Mordenkeinan isn't "True Neutral." He's Neutral Evil. Anyone who is Militant Neutral in D&D is.
Moral relativism is how Neutral is described in I think from 3rd ed onward. Which makes sense overall. Its why most people in DnD are neutral now. But thats not militant neutral, which by ethos, is just as likely to enslave people as it is to liberate them purely to keep the numbers balanced.
BTW, I think this right here is where the problem comes from originally.
The idea of needing a dynamic between law and chaos for things to work makes sense. So when your alignment system only have that one axis, the existence of a "militant neutral" ethos makes sense. But in terms of Good vs...
The Lady of Pain isn't a human being so moral contsructs around their behavior are vague. There is no indication their motives are "Uphold balance between alignments." It is "By any means possible, avoid disruptions to Sigil." I would argue The Lady is LN anyway.
As I state initially, saying "Unchecked Good can lead to Tyranny" is a facile argument because by definition when that happens it is no longer Good, it is Evil.
So Im not arguing Good or Evil as they exist in our world where their existence is something people enjoy debating. I mean in D&D early editions, they are a real game mechanic. They are a metareality both in setting and in the game's systems.
I will regret this, but meh.
So are there actual lore examples of "True Neutral" NPCs and their actions that have any justification for their positions beyond something supernatural, ie "good" and "evil" are fundamental forces that must exist in some degree of balance to maintain the spiritual...
Yeah sorry. Sematic arguments are well loved online but they can jog on for me. My position is just that, mine. It informs how I try to run games and what frustrates me when I am a player in someone else's. It's that simple.