While I agree with the general point you make, I think it is a mistake to say race or caste is a proxy because it gives the impression that there's a "genuine"

While I agree with the general point you make, I think it is a mistake to say race or caste is a proxy because it gives the impression that there's a "genuine" order of things behind the curtain of illusions. This is not a good model for a better understanding of the world around us imo. Hierarchies whether based on material resources or status seems to exist everywhere but are instantiated differently in each place for historical reasons. Race or cast is not a proxy for real hierarchies hidden behind them, it is how some of those hierarchies have taken form at some point in history (and will hopefully disappear at some other point). As the anthropologist Maurice Godelier puts it in the L'idéel et le matériel, it is not about seeing another reality behind reality but about seeing the same reality with a different look.