Often times it seems within ATLA’s narrative whether Fire Nation characters are “good people” is determined by how nice they are to Zuko or how nice they are to people who are nice to Zuko, not by any of their other actions. This is definitely true with respect to fanon and within the the fanbase.
There are four Fire Nation characters which violate this rule, notably with three of them being from Book 1. These are clearly good people, and are presented as such, without having a real connection to Zuko or Iroh. They are Piandao, Jeong Jeong, Shyu, and Chey.
However, beyond that a certain pattern becomes clear. Iroh inflicted decades of imperial violence upon the world and isn’t being very proactive about stopping imperial violence in the present(he even gives Zhao good military advice during Zhao’s attempt to conquer the Northern Water Tribe!). He’s nice to Zuko, so from the beginning(long before his White Lotus connections were added) he was always presented as a “good” person, and the fanbase thinks of him as perfect.
Lt. Jee and Zuko’s crew become respectful and nice to Zuko once they find out about Zuko’s backstory, so they’re presented sympathetically and as “good people” from that point onward, and Lt. Jee tends to be positively depicted in the fanfics where he shows up. Never mind that helping Zuko at that point involved inflicting imperial violence on world...
Zuko and Iroh loved Lu Ten, and I believe we’re supposed to believe that Lu Ten loved Iroh and Zuko back and was kind to them. Lu Ten is framed entirely sympathetically, and in fanfiction he’s almost always presented as “a good person.” Never mind that he was an adult soldier who died fighting in an imperial war of aggression.
Ursa laughs at the thought of Ba Sing Se burning to the ground, and if we look at her original intended backstory, it becomes clear that she must have supported the war. The decision she made to murder Azulo and support Ozai coup is also responsible for the Big Bad of the series being in power, although she didn’t exactly have good choices there. Yet, because she was a good mother to Zuko, she’s almost always considered a good person by the fanbase, and the narrative frames her as angelic.
Ming, the guard who was nice to Iroh, is almost always presented positively in the few fanfics she shows up in(maybe one of the reasons she’s so kind to him is because she thinks very positively of his achievements as Dragon of the West? That would be an interesting take).
Mai commits treason to save Zuko’s life and is generally kind to him, so she’s “a good person” and not a morally grey character according to the narrative and fanbase, even though she voluntary joined up with Azula for her own enjoyment and regarded engaging in imperial conquest as an enjoyable hobby. Definitely there are very few fanfics which grapple with what she did during the war and why she did it.
Ty Lee is always nice to Zuko, at least in their two canon interactions in the present. More importantly, she commits treason to protect Mai, who committed treason to protect Zuko. That marks her as “a good person” in the eyes of the narrative and fanbase, even though Ty Lee was clearly shown as having a blast helping Azula engage in imperial conquest. Like with Mai, there are very few fanfics which grapple with what she did during the war and why she did it. Remember, the Dangerous Ladies conquered Ba Sing Se together(and with Zuko’s help, of course).
On the other side, we have Ozai and Zhao, who are mean and awful to Zuko and are painted as evil for it. In fact, the thing what really confirms their awfulness in the eyes of audience is how mean they are to Zuko, not any of the other heinous stuff they did. We also have Azula, a younger sister who made the unforgivable mistake of being nearly as mean to her older brother as he was to her.
It’s funny, though. On one hand we have Zuko, Piandao, Jeong Jeong, Shyu, and Chey. These are people who had to fully come to terms with how awful the Fire Nation actions are and how their own actions aided the Fire Nation’s war of conquest as part of the process of becoming good people. If I’m generous, I might throw Iroh into this pile.
On the other hand, we have Lt. Jee, Lu Ten, Ursa, Ming, Mai, and Ty Lee. These are “good people,” according to the narrative and particularly the fandom, because they were nice to Zuko or Iroh, even though they played their own roles in perpetuating the Fire Nation’s imperial war and never came to terms with it.
Dare I mention that many Azula “redemption” fanfics center entirely on her becoming a better sister to Zuko? Dare I mention that the head writer of ATLA’s ideas for an Azula redemption arc seems to center around Azula becoming a better sister to Zuko and a nicer person, not with her coming to terms with the Fire Nation’s imperialism?
It seems like ATLA’s narrative and fandom suffers from a case of deuteragonist-centered morality. Which is funny, because for the first two and a half seasons Zuko was a villain and “being nice to him” or “being kind to him” would frequently involve helping him do bad things, or at least allowing him to bad things.
