I think a step back from the word itself, quibbling over definitions, and looking at the behavior might help people actually talk to each other instead of talking past each other.
There's a style of play or character creation called XYZ. Like most things, XYZ exists on a spectrum.
You have the anti-XYZ people who make choices that are diametrically opposed to the ethos of XYZ. Let's say these people are on the negative side of this spectrum/number line.
You have the neutral to XYZ people who make choices regardless of the ethos of XYZ. Replace regardless here with orthagonal to or that don't interact with, etc. Let's say these people are at the zero mark on this spectrum/number line.
You then have the pro-XYZ people who make choices that follow the XYZ ethos. Let's say these people are on the positive side of this spectrum/number line.
But, given that this is a spectrum, there are levels of XYZ to consider. The minimum XYZ would be something minor and basic like picking stats and skills that complement your class in a class-based game, e.g. a wizard with high INT. Let's say these people are at the +1 mark on this spectrum/number line. And it would go up from there. The more intense the XYZ, the further along that spectrum/number line you get.
While some might quibble with the idea, I think most could agree that the extreme end of this spectrum/number line (let's say +5) is the wildly game-breaking stuff like Pun-Pun, etc. Trying to slap a different name or label on it only confuses matters. It's only different by extremity not category or kind.
When most people in this thread say they dislike XYZ, they're talking about stuff in the +4 or +5 range. Likewise, when most people in this thread defend XYZ, they're talking about stuff in the +1 or +2 range.
It's also worth remembering this is about what shows up at the actual table, not white-room theorycrafted characters. People aren't complaining that XYZ exists in the abstract, they're complaining when something in the +4 or +5 range shows up at their table.
This is thoughtful, let me try to respond in kind.
Let me talk about poker for a second. A big facet of poker is probability. But another big facet is psychology - reading opponents, bluffing them that your hand is stronger or your hand is weaker, convincing them to bet more when you will win, convincing them to fold when you aren't sure you can.
However, if you've ever played poker for fake stakes, like chips with no value outside the game, you might have encountered the player that's not there to win. Regardless if they are just listless, or chaotic, or whatever, they play in such a way that invalidates that second facet of the game. Which ruins it for other players.
Now, we all know the G in RPG stands for game. Some games like D&D are very much about character success because the most common stakes for overcoming challenges is death, which isn't fun when it's the characters dying. Other games may not be like that, let me stick to D&D-type games for a moment since that's where this discussion seems most centered. We wouldn't have having this discussion in a game like Marvel Heroic Roleplay where characters are not expected to be balanced against each other and the system handles it just fine.
To optimize is to make effective use of resources, situation, and opportunities. I just quoted the definition from a dictionary in my last post.
To be on the "dislike-XYZ" axis, that means that they actively do not want to do those things. They actively want their characters to fail.
And much like the poker example, that ruins the fun for the other players as well.
So what we have left is people who have no passion for play or are just here for the chaos -- neutral XYZ in your terms -- and people who want their characters to succeed. And here we have the spectrum from mild to extreme.
Frankly, I try not to play with those who don't care about the outcome, but I understand that's not always everyone's preference, like a friend or family member or significant other who needs be included for non-game reasons.
So the question is "is everyone close enough to each other on the spectrum of wanting to play well mechanically that everyone has fun"?