Recognizing a difference where there is one does not cause segregation based on race.
If we have to choose a causal direction, I'm pretty sure it goes the other way. Otherwise we'd say things like "The government are trying to take my job away." (what British English speakers would say) to suggest someone is stupid, but no one does. That sentence, from my American-English perspective, sounds just as "different" as "The government be trying to take my job away.", which is grammatical in Black English.
If we have to choose a causal direction, I'm pretty sure it goes the other way. Otherwise we'd say things like "The government are trying to take my job away." (what British English speakers would say) to suggest someone is stupid, but no one does. That sentence, from my American-English perspective, sounds just as "different" as "The government be trying to take my job away.", which is grammatical in Black English.