That's not what a Nazi is. That's an authoritarian. All Nazis are authoritarians but not all authoritarians are Nazis. Nazis didn't and don't do the horrible things they do because they're authoritarians, they do them because they're extremist ideologues; their particular brand of authoritarianism emerges from that ideology.
Authoritarianism, on the other hand, could come from a genuine place of wanting to keep people safe. That doesn't make it right or admirable, but the impetus behind it is not harmful, only the way in which that desire is enacted.
By saying they're the same thing, you're playing their game where Nazis can hide behind the less extreme term.
You can be anti-authoritarian without being needlessly hyperbolic to the detriment of the point you're trying to make.