If you have not studied communism, and your main contact with communism is tankies on Lemmy and “communist” dictatorships in history, then I understand why you would think that.
But communists by and large are not tankies, and do not wish for states like the USSR, China, or North Korea. Those people typically identify as Marxist-Leninists (promoted mainly by Stalin after Lenin died), and yep they’re authoritarian, and they’re loud. And, despite the name, Marx himself would disapprove of this ideology for a number of reasons.
Read even just the first paragraph of the Wikipedia articles on ”Communism” and “Communist society.”
A communist society would entail the absence of private property and social classes, and ultimately money and the state (or nation state).
Communists want no state; it is effectively a type of anarchist or radically democratic ideology, where the citizens all equally share power through common ownership of industry… the very opposite of authoritarianism.
A communist society is characterized by common ownership of the means of production with free access to the articles of consumption and is classless, stateless, and moneyless, implying the end of the exploitation of labour.
The term communist society should be distinguished from the Western concept of the communist state, the latter referring to a state ruled by a party which professes a variation of Marxism–Leninism.
Communism is not an authoritarian philosophy. If you go talk to people in real life who identify as communists, you will tend to find communists as described in these articles. If you look on lemmy.ml, however, you’ll find lots of Marxist-Leninists (tankies) because that’s who the instance was made by… but that’s not really representative of communism as a whole, and many communists find that philosophy repulsive.