If the point is the story, what purpose does the model/simulation serve? In this case, the best that the model does is prove that the story is internally consistent. It doesn't prove that the story has any relationship to reality, because there are hundreds of other stories about segregation that you could tell, each with their own model.
It serves the point of illustrating that a common belief about how segregation and level of racism in the population does not hold together: More segregation can occur even with beliefs we would not consider racist; all else being equal, reducing, or even preventing the increase of, segregation takes far more than absence of racism.
