Some of them think that communism is so perfect that any communist state (i.e. a state that plans to build communism one day, but doesn’t claim to have done so yet) can’t backtrack and will only get closer and closer to communism over time. Claims that Russia is no longer communist, and is just an authoritarian capitalist oligarchy, must therefore be lies made up by the west to trick people into not trying to build communism here. Russian troll farms will find communities of people who think this, and make posts agreeing with them and telling them that everyone’s super happy in Russia and anything bad is made up.