Dont forget the comics where they decided that instead of returning the fire nation colonies back to the earth kingdom they should instead form a new nation out of stolen land
Earth Kingdom peasants rise up against the king for better conditions. The king asks Kyoshi, the avatar before Aang, to suppress them. Kyoshi won't serve the king at first, but then some windows get broken or something and she goes full cop and suppresses them, then further goes on to establish the Dai Li secret police to prevent further protests.
The "wisdom" being that the avatar answers to no king, but destroying private property is even worse, so some weird centrism is the best . In general, the Avatar is a disgusting centrist neoliberal corruption of the original Indian concept of a hero incarnated to deliver divine justice for the oppressed
Korra had so much potential with this sort of stuff, the third season with the anarchist villains in particular. People actively challenging the idea of the avatar because they just defend the status quo and the rich and powerful could've been a fantastic series that actively challenges neoliberal ideas of power. Sadly we got the "pro-neoliberalism" avatar sequel.
Toph becoming a cop is actually a materialist reading. She's a noble who went through a rebellious phase as a child, not even a teenager. Her material conditions brought her back to her wealthy, exploitative upbringing. Her proximity to several leaders of nation states, her family wealth/status, and her literal "only person in the world" metal powers brought her to the natural conclusion that she needed to preserve the powerful elite she and her friends were part of. Naturally as an innovative, intelligent, and adventurous person she saw how the old world system was transitioning into bourgeoisie capitalism and instead of getting swept away with the old aristocracy she secured an essential position as chief defender of capital.