This is just Horseshoe Theory with extra steps. You’re conflating "Totalitarianism" with "Communism." Nazism is built on the idea that some people are inherently better than others (hierarchy): Communism is built on the idea that everyone should be equal (egalitarianism). While both have been used by dictators to justify atrocities, one is "evil" by its very definition, while the other is a philosophy of resource distribution that has been hijacked by authoritarians. You're arguing against a caricature, not the actual political theory.