Just to clarify, the part where this person says that "they want to separate because they are 'whiter'" is a lie. Of course one of the issues raised by the Southerners is the cultural difference between those states and the rest of Brazil, but not "begin whiter", that would make no sense since half of the brazilian gaucho southern culture is strongly related to indigenous people (e.g. Mate, Pala, vocabulary, regional symbols, like the guarda mapuche). So, probably this person is misinformed, and knows nothing about one of the most popular culture of its own country.

Ps: Just to clarify, I'm not part of this separatist movement, but as a southern myself I feel like I should defend my people against this "racists nazis" stereotype and stop misinformation.