I've read the series twice, so using the exact descriptions of the late Robert Jordan, I have conjured images of the characters in my mind. Diversity for the sake of diversity is not a bad thing. After all, John Wayne portrayed Ghengis Khan in the 1950's movie "The Conqueror". lol. Black actors portray our white founding fathers in "Hamilton".
Having said that, I don't think I'll be watching. Most books translated to the small or big screen suffer from meddling re casting, writing, direction, straying too far from the author's direction, and a whole host of other situations those in front of the camera and those behind it fail to translate. I will avoid the sure and certain disappointment, at least to me, by not watching.