What about equal rights is pluralistic?
Much of the civil rights movement was fighting for equality against an ethnocentric backbone that had access to the rational sphere where the African Americans did not. I would argue that this fight was more similar to The Enlightenment shift, than it was to a shift from rationalism to pluralism, and so therefore was a shift from ethnocentrism to rationalism.
To me the aspects of the civil rights movement that WERE pluralistic were reparations, and affirmative action. These types of arguments argue for shifting the playing field such that it is not only flat, but weighted in the favor of the historically oppressed in order to flatten it forward in time.