The Leftist media is caught in a dilemma with respect to South Africa. For decades, they were preaching that racism must be defined as "Prejudice + Power". In other words, only those with power can be designated as racists, so blacks can't be racist because they have no power (never mind that a black mugger with a gun to your head has all the power in the world with respect to you).
This creates an issue when a country where blacks are in complete control of the power structure oppresses whites. By the Left's own preferred definition, these people are behaving in a racist manner towards whites. Therefore they pretend it doesn't exist.
The way they treated white farmers was shameful, especially considering that in Zimbabwe they did not have apartheid and the communities lived in pretty much harmony.