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It could fall under Fantastic Racism
I do some cleanup and then I enjoy shows you probably think are cringe.
Never Be Hurt Again? It mentions the Ur-Quan from Star Control under Video Games, who were turned into mind-controlled slaves by the Dynarri and now seek to enslave/exterminate (depending on the faction) all other sentient life. Dungeons & Dragons'/Planescape's githyanki have a similar history with the mind flayers, and are highly xenophobic (but largely limited to launching interdimensional raids rather than slavery or genocide).
What would this be? I'm thinking a combination of Absolute Xenophobe and Freudian Excuse.