Porn producers (AKA nearly all yew-ish guys who have never even set foot in temple) deliberately set the scene like this. They cast a thousand black guys and pick the 3 biggest ding dongs. Then find the smallest white guys willing to degrade themselves (liberal hiveminds).
Not true. The white porn guy almost always shoots the biggest and messiest cumshots and that's what gets the attention while the black porn guy is wanking and wanking and nothing comes out but drip dribble and ooze.