Nazi isnt a word that is banned on its own typically.
Accusing someone of being a Nazi? Probably should be banned for that, unless you have actual evidence of the person youre accusing endorsing the specific policies of Nazis. Throwing that word around just to describe anyone you disagree with or doesn’t agree with you is quite frankly incredibly disrespectful to the people who had to suffer at the hands of actual Nazis, whether they are still alive or not. It cheapens the word.
Speaking in a historical context? Definitely shouldn’t be banned for that.
At the end of the day, it depends on the moderators of the instance and community. There is no guarantee anything you say or do online will prevent you from being banned. Even if you follow the rules.