In Capitalist countries authority is used to oppress the masses and protect exploitation, in Socialist countries it is used to oppress the Capitalists (who don't just disappear the second the revolution succeeds), the CIA invented "Authoritarian" as a way of demonizing Socialist countries by drawing attention to how it suppresses the class enemy of the working class rather then who is suppressed and for who's benefit. A State is needed for as long as class antagonism exists, which itself will exist as long as class itself exists, which itself will exist so long as the material conditions for classes exist, which will exist until global communism is achieved. Until then, a State is needed to protect the success of the revolution, which is "Authoritarian", along with your brain telling your body to get up in the morning, the bullet from a gun used against fascists who do the same to you, or even missiles used to deter the U.S. from bombing the shit out of you which they have done before and would do again. TL:DR "Authoritarianism" isn't a thing.