I think the point Nikita is making is that the Matari are tribal and much of their culture (aside from naming conventions apparently) seems to find its base in South American/South African tribal cultures.
I realise you're trying to clarify a point someone else is making, so take the "you" in my reply as a general thing covering anyone actually claiming this.
Can you share any sort of evidence -- even suggestion-type stuff rather than hard stuff -- to support this?
Why do you think that much of Matari culture seems to find its base in South American/South African tribal cultures?
As an example of the sort of supporting evidence that would be useful, there's a book
The Art of EVE which (apparently, I haven't seen it) says the Brutor were originally inspired by Maori. That confirmed my impression based on
the early race description that they were Polynesian: island navigators, tribal society, tattoos including facial whorls,
mere-shaped ear pendants, and if you were making generalisations you could apply most of the same physical descriptions.
Now, based on what I've seen coming out of CCP more recently I think things have changed a little since then so I wouldn't want to advance Maori as 'the' way to play Brutor, but I think if anyone were looking for a real-world inspiration it's the culture that has the most support. Similarly, for 'general' Matari culture, and especially for Sebiestor culture, there's a good case for drawing on Old Norse elements, and there's some lovely stuff you can do with ritual, spirituality, loyalty, and bloodprice.
If you're going to assert that Matari culture seems to find its base in South American/South African tribal cultures, and particularly if you're suggesting that others should take this idea seriously and consider it for inclusion in their play, I'd like to know
why you think that.
If you just happen to like it and want to use it in your portion of the world, go for it, just please don't present it as though it's more than your preference.