R you saying this from an american perspective?

This idea is referred to as "Circulation of Elites" and suggests that every ruling-class has to be a minority group (E.G WASPs in USA, Normans in medieval england, "the rich" in general in most places), but they will always end up being displaced by another minority group. Because the key to securing power over, for instance, a country, is to be highly organised (only possible for a small, organised minority - never a/the majority group) and when in power, this group becomes complacent, so their grip over power slips and in comes the new elite minority ruling class

historically this is often identified/misidentified as Elites mixing, sexually/culturally, with majority groups or other groups. This is more usually a symptom but it could in some cases be the cause. The opposite - Inbreeding - is of course also bad, as is a refusal to learn new ideas (i.e refusal to mix culturally).

So... it's like a law of nature. Whatever elites do they slip out of power sooner or later. American elite have probably been in power for a "healthy" amount of time tbh.

just in case it's not clear, minority does not mean racial minority here. It's literally any group that is small and organised - christians or atheists, rich middle class or gangsters.