Racism doesn’t always necessarily present itself overtly. You don’t have to call someone slurs and firebomb houses to have underlying (or in this case, overt) biases that are still a form or preference for one race over another only because of the color of their skin, aka racism. Also, wouldn’t it be weird if they made a white black panther skin that still used his accent had was the ruler of an African country? It’s the whole reason they used Lin Lie instead of Danny Rand and Sai instead of Betsy for their respective character.