Honor cultures are just a social framework where shame is used as a method of community control, which is usually tied to material penalties - be that from exile to being shunned from new business opportunities. It doesn’t imply any specific set of morals and it doesn’t necessarily prescribe any particular set of actions - it just means that there is some accepted framework for behavior. For being dishonored to mean something you have to be in a position to be shamed/punished for that. Honor doesn’t directly protect anyone not in the framework that enforces honor, because who cares about the opinion/disapproval of someone in the outgroup?
What “honor” means in genre convention, though, is very different. It means that when someone does something the narrative frame condemns, they regret it (if they are meant to be good) or revel in it (if it is meant to be bad) - and strictly speaking this is not grounded in any moral framework other than the fictional ethics of the character and the writer’s own biases.
This is why Orcish honor is so schizophrenic, because it’s a genre convention used lazily to signal authorial approval and WoW has no consistent authorial voice or concept of how Orcs function as a society.
For example: Eitrigg is honorable. This means, in the fiction’s logic, that he is good. His noted honorability is part of his framing as a ‘good’ guy we are meant to sympathize with. This is decided before he actually takes any action. This is why Eitrigg, honorable Orc, has the player “help” the Blackrock summon a pit lord only to then unleash it on his former clan to burn them all to death in hellfire. He also has the player stab a bunch of people in the back, literally, to kill off those who are in the way of this plan.
But remember, Eitrigg is honorable. That is pre-supposed, it’s one of his defining traits. So that cannot bend - therefore, the meaning of honor changes instead because it is nebulous by its nature. So we end up making excuses like ‘well the Blackrock clan has its own kind of honor…’, etc.
Because ‘Honor’ is such a nuanced, context-specific concept IRL and because it relies on a consistent authorial moral vision in fiction, it becomes utterly untenable in the context of WoW. It ends up having to constantly be in a state of revision and re-adjudication, which is how we end up with MoP2, why we will likely get MoP3, etc.