Yeah true, then it works.

Endonyms often turn out to derive from “people” in some language or other, but exonyms could come from anything like “the people on the other side of the hill/river/swamp” or “the rich people” or “the people who herd sheep” or “the people who really like goat’s milk”. There’s an inherent asymmetry between naming the one group of “us” and all the groups of people who are not “us”!