“the rise of populism as a powerful faction within the Democratic party has come at tremendous expense to the factions that were centered around those issues… - who have definitely lost some of their power within the party, but not nearly as much as the Greens and the minority rights coalitions.”

Let’s talk black politics, since you keep hinting at it. The elderly civil rights coalition succeeded in creating openings for educated and monied black people but has done little for the vast majority of working class black people, especially less well educated black men. Indeed this civil rights elite is often aligned with the white elite in moralizing the problems experienced in poor black communities. This is why younger black voters are getting behind progressive candidates, AND WHY MANY OF THOSE CANDIDATES ARE PEOPLE OF COLOR.

Your mistake is insisting that these issues of civil rights and environmental justice are separate from the dynamic of class inequality and wealth concentration. They are not.

While you can address the opportunity structure for some minorities through policies aimed at racial equality, you’ll never achieve for all unless you attack the class inequality at the root of racial privilege.