Let’s get one thing straight.
Nazism doesn’t exist in the Star Wars universe.
Nazism is a very specific ideology that relies on the genocide of the Jewish and Roma people. This ideology does not exist in the Star Wars universe.
Nazism isn’t shorthand for “bad” or “evil.” Are there visual parallels to Nazism in Star Wars? Yes. But that’s all they are – ideologically, they are very different. There are also visual parallels to communist regimes, or really any dictatorial regime.
Using “Nazi” for shorthand for “bad” or “evil” detracts from the seriousness of Nazism and neo-Nazism, an actual problem we are facing in the real world today.
Think twice before using the word “Nazi” to flippantly describe a fictional character you dislike.