Communism is inherently authoritarian. Essentially the voluntarism aspect on scales on the level of something like Israeli Kibbutzim. As soon as you go larger than that, you need the boot-heel of the state to enforce it.
There's More than one kind of communism. Yes state Bolshevik communism is inexorably tied to authoritarianism. But the fact that you can't imagine a communism that isn't. Isn't a problem or failing a communism. It's a problem or failing of your understanding /education. So I am quite interested for you to explain it to me how small c communist style communes etc such as hippie communes Bohemian communes are inherently authoritarian. Good luck!