Both sides calling the others Nazis doesn't imply that centrists are using critical thinking. It just means that one side is lying. Nazism is a far right ideology.
"Never believe that anti-Semites are completely unaware of the absurdity of their replies. They know that their remarks are frivolous, open to challenge. But they are amusing themselves, for it is their adversary who is obliged to use words responsibly, since he believes in words."
What is it "Tankies" advocate for that is "totalitarian?" The term "tankie" is the new "woke," it's a strawman and a bundle of contradictions based on misinterpretations, misunderstandings, and being entirely unfamiliar with Marxism.
I suggest reading Blackshirts and Reds, Communism and Communist movements are and have historically been entirely different in aim, goals, practices, and context from fascism and fascist movements.