Regarding color, I think you're at least a decade late. Eminem released The Slim Shady LP in 1999. Then you got Beastie Boys, Aesop Rock, El-P, Atmosphere, etc.
Let's not forget 3rd Bass, Cypress Hill, House of Pain, etc. White rappers have been around forever; to act like they're some sort of new or even remotely rare phenomenon is kind of silly at this point.
By 1999 Beastie Boys had 5 LPs under their belt
Yeah, Beastie Boys are huge, but Eminem is a superstar.
I'm just pointing out what the perception might be which caused the author to pick that headline. Plus, really you can only pick a handful of successful white rappers, for the level of success we're talking about here. Black rappers are far and away the majority.