Ya know, there are a lot of persons of color who get shit on by mouth breathing idiots for speaking their piece on issues of race and having their opinions discredited as insincere or opportunistic.
I'd say that, for about 99% of those people, it's bullshit and just a way for people who are naive, uninformed, or outright racist to shut them down. But one person for whom I think the criticism rings somewhat true is Jemele Hill. She's currently opining on a 6-year-old video of Louis CK and Chris Rock using the n-word on Twitter and moreover misrepresenting (whether intention or not - she could just not be bright enough to have picked up on the suggestion) Ricky Gervais's reaction to a joke by CK about how, in pairing up the four (CK, Rock, Gervais, and Seinfeld), CK/Rock used the word on stage, while CK/Gervais used it in private (making the joke that Gervais and CK were actually racist in private). She commented on how Gervais was "proud" that he used the word in private.
Not gonna link her tweets, so this is the original video