The only advice Aang doesn’t take is Yangchen’s
Something that struck my while re-watching Aang’s discussions with the four past Avatar’s is that when he take’s Ozai’s bending away he is technically following all of their last words of advice except, ironically, his fellow Air Nomad Avatar.
Roku: You must be decisive. Aang is so firmly committed to not kill Ozai in cold blood that he pulls himself out of the Avatar State. The Lion Turtle also warns him that in order to successfully bend another’s energy “your own spirit must be unbendable.” Aang was firm and committed to his decision to find another way.
Kyoshi: Only justice will bring peace. Justice isn’t inherently a death sentence. Justice means consequences for one’s action in a punishment proportional to the crime. Ozai did need to be punished after all of the pain and suffering he inflicted on countless people and threatening the balance of the world itself. And he was. All things considered, what is a more fitting punishment for someone as self-absorbed and power hungry as Ozai: Dying in battle, going down in history as such a powerful warrior that it took the Avatar (channeling every past Avatar) to best him or having to live out the rest of his natural life without his status and bending (the two things he valued most) and watching as all that his cruelty and imperialism created was systematically dismantled? Also a point I can’t take credit for this interpretation and don’t remember where I read it from but fully agree with: making the choice he does Aang proves that the Air Nomad culture and values were not destroyed. Going back to the crimes of Ozai’s forefathers, Sozin’s legacy is proven to have failed to truly eradicate the Air Nomads and ultimately it is their philosophy of peace that wins the day over rage and violence.
Kuruk: You must actively shape your own destiny and the destiny of the world. Similar to the point about decisiveness- Aang makes his own choice. He doesn’t passively accept what literally everyone is telling him the only possible outcome is. Instead, even as he seeks advice he insists on his own autonomy, recognizing that whatever action he takes will change the course of the world and its destiny. He very much took an active role in deciding how that battle ended and what came after.
Now finally we have Yangchen. While, in context, yes all of the Avatars felt they were telling Aang to kill Ozai they all choose phasing that as illustrated above is actually open to wider interpretation and still holds true with what Aang actually does. Yang Chen is perhaps the most direct in her advice: Selfless duty calls you to sacrifice your own spiritual needs and do whatever it takes to protect the world. The one thing Aang does not do is compromise his own spiritual beliefs and identity. He finds a way that upholds his responsibility as Avatar to restore the balance, prevents the destruction of the Earth Kingdom, and mete out justice for past crimes all while still honoring the beliefs he was raised on and holds so dear.
