This has circulated without what I think is important context: Musk’s tweet is a reply to Massimo (who AFAIK has never shown Nazi tendencies), who was musing about how lemurs diverged from other lemurs 88M yr ago. There is, therefore, a plausible innocent context for his tweet. It seems that his Nazi fans, though, saw this as a shout-out. And that’s how these things work: Musk can claim innocence—and we can never know his motive—but Nazis saw something they liked.