The german version of RimWorld currently contains the word "völkisch", a term invented by the Nazi-regime for propaganda purposes, which should not be a part of this game.
Your interpretation is only partially right: "völkisch" was indeed used by the Nazi-regime as a specialized word for the national identification, but the word itself is much older as you can also read up on wiki:
https://de.wikipedia.org/wiki/V%C3%B6lkisch
Nonetheless, I don't see a problem with changing it. Will be done. :D