Why is one inequality different?

The contrastive link at the end of the post immediately beneath this one is to a piece reflecting on the 'march toward democratic inclusion' of so many groups in the US - blacks, women, Hispanics, gays - at the same time as economic inequality has grown; so that general inclusiveness goes together with continued and indeed more pronounced economic stratification. The writer, Alexander Stille, compares that development with what has happened in Europe. But what struck me about his article is that he nowhere notices, or at any rate he nowhere mentions, what to me seems an obvious point: namely that, in a society structurally centred on economic inequality and constantly reproducing it, an equalizing inclusiveness is in principle capable of eliminating all forms of inequality but one.