They've specifically said they're using people of color to avoid "whitewashing" like the Movie-That-Must-Not-Be-Named.
Except... Zuko and Iroh were like the palest people in the show, but were cast with Indian actors, so I'm a little confused about their SJW whining about Katara and Sokka.
Except... Zuko and Iroh were like the palest people in the show, but were cast with Indian actors, so I'm a little confused about their SJW whining about Katara and Sokka.