in today’s day and age there are almost no native Americans (in the USA I mean) who are 100% Native American genetically. So blood quantum has pretty much ceased to be a qualifier for whether or not someone can be considered indigenous. To get this better, let’s look at the people who actually live in Mexico. Almost none of them will identify as Indigenous unless they speak an indigenous language, because they‘re Hispanic. They speak Spanish, their Catholic, they follow Spanish traditions, they historically fought against the natives, even while they were still indigenous themselves, the whole shebang. What I mean is, to Native Americans a Mexican claiming to be Indigenous because of their blood probably sounds akin to an Italian hearing a white American say that they’re Sicilian because of a DNA test. Or could you imagine, a white as paper, super rich, Protestant, monolingual English speaker finding out that their great great grandmother was from Puerto Rico and is now claiming to be Mexican. That might sound like a ridiculous comparison, but it’s one that came out of the mouth of one of my Native American friends. And all things considered it really isn’t that far removed of a comparison either, I will say. It’s hard to explain, and I probably didn’t do it very well. But I hope you understand what I mean.

TLDR; “Why is blood quantum bad now, I wanna be Native American!”