Why are you using a slur in your example? That seems unnecessary.
Ideally I would've wanted a Cheyenne actress for Moonstar yes. What you are describing is ethnicity vs colorism. No, not all tribes are the same and neither is racial ancestry.
The black community in the Americas themselves are made up of various African tribes that have different genetic ancestry and cultures, that sometimes can vary wildly from group to group. The same applies to Native Americans. This is why race is in part considered a social structure due to how society or groups in power have classified people based on their skin tones less than true ancestry.
So yes, considering the power dynamics involved I would've been fine any actress that was plainly "Native American" even if she was not specifically Cheyenne. Just like I would've been fine any with black actor for Sunspot or Cecelia Reyes despite not knowing exactly what part of Africa his ancestry might have come from. Minority groups from the Americas have, at times, formed a monolithic identity group as a combination of protection and shared experiences enough for me not to be that bothered when casting choices are not completely 100% accurate; some not even completely aware of their own ethnic history due to years of oppression. However Hollywood in general could strive to be more ethnically accurate as well, as they
have shown the ability to be more culturally aware... but only when money is involved such as Fox trying to get Chinese audiences money with Fan Binging.
Except mestizoes or "halfbreeds" are the dominant racial and ethnic group in South and Central American countries. Facing racial discrimination for being a "half-breed" for native ancestry makes no sense and again, Roberto is clearly Afro-Latinx in his history. It's clear CC was portraying racism toward dark-skinned (afro-latinx) latinx people in Brazil.
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Edit you clearly had this conversation with another poster several days ago, I don't know why you are saying Sunspot looks native when the artist and script have him portrayed --- and stated
ON-PANEL --- that he is black.
Can you please stop being disingenuous here?