The defining theme of Sinners to me is assimilation of non white people by whites. With the head vampire even saying at the end that he remembers the same thing happening when the English took Ireland. The identity of the black clientele feels completely erased, down to cornbread's accent changing when he tries to get back in. The turned club goers dancing an Irish jig feels to me like erasure of culture with the delta blues being thrown aside for traditional irish music. It's also telling that the first vampire to initially access the venue is the one white passing patron and she immediately infects one of the black entrepreneurs, maybe referencing later cultural dilution as a result of intermarrying but that might be a reach and I can't really speak to that directly.