I found an article with Indigenous criticism of Avatar: Fire and Ash (Three movies in, has Avatar gotten Indigenous representation right?).
Sarah-Tai Black confirms that this film is unjustifiably shallow, and a poor representation of Indigenous cultures:
One thing I was really thinking about, as someone who is completely new to the series, is … the violence and the language of the film — not that there's a lot, but there's enough to signify that these films are directed for adults, for teenagers, for mature tweens. But if that is that, why is it that its story world, its characters, the relations to one another are all so lacking in depth and impact?
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I was thinking a lot about Killers of the Flower Moon while I was watching Fire and Ash, and how, in my opinion as a Martin Scorsese lover, he should not have directed that film. I think there's a lot of colonial violence being reenacted by that film. But there's also a few moments in that film here and there where Indigenous being and Indigenous spirit kind of breaks through…. There's none of that in the Avatar movies. Cameron doesn't even care to give us those moments of lived life.
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I just felt there was no heart. There was no spirit. There was no soul to this film. I felt nothing. I didn't even feel anger. I didn't even feel, like, contrived sadness — and I am … an easy cry. I love the cinematic emotional manipulation. And since I got out of the screening of Fire and Ash last night, I've just been thinking about, like, what is the political function of all of that?
Jesse Wente confirms that these films aren't actually anti-colonialist, but are rather colonial fantasy:
But if his intent is to have some sort of reckoning with colonial history, I mean, these films are an utter failure. And I don't actually think that is the intent. To bring about language I used in my original review 16 years ago, these films are colonial fantasy. These are movies where non-Indigenous people embody Indigenous people, and become the heroes of the story. This film is not about Indigenous people. All of the central characters, save for the women — which is an interesting thing that one might really want to think about, in terms of how Indigenous women are so often the targets of colonial violence, and yet they're the only Indigenous folks really at the heart of this story…. The hero men in the story are not Indigenous. They're all non-Indigenous people in costumes. That is a fantasy. And not only are they in costumes, they're our leaders….
Once again, if white people want to learn more about Indigenous philosophy, Potawatomi botanist Robin Wall Kimmerer has published books you can read, and you can find speeches and interviews with her on YouTube. You can also search YouTube for "Indigenous ecology" and find a lot of stuff worth watching.