The identity politics Democrats engage in is fundamentally Marxist. Plug in dichotomy

To that extend the OP is a Marxist. He's focusing on the dichomtomy.

Collectivism

Ideologically postmodernism leads to the acceptance that Black people can live in a Black community and don't have to integrate into White society. Ideologically today's left puts value on protecting native cultures and doesn't believe in pushing modern Western cultural values on other societies.

That's very much against Marx idea that everything is supposed to come together.

Today's left considers that everybody is entitled to his own identity and there no need for individuals to integrate into the collective norms of identity. There's no belief that there one correct identity and that if history finally advances to communism everybody will have that collective identity.

Diversity ideologically valued when Marx didn't value it.