Equal society or Tyranny of the Clique?

Judging from what the fine intelligent patriotic intellectuals in our left politics (and across the globe) say about communism being the best politico-economics system that really fosters equality and liberates mankind from tyranny, I wonder why all communist countries so heavily repress their own people?
And to those who counter this by saying that no they don't its merely the pro capitalist media that spreads disinformation I'll ask if that is true why do countries like China have so much state control over media, do not allow foreign journalists (or human rights workers since journalists apparently are all rabidly pro-capitalist) to freely interact with people?
Why are communication channels so heavily controlled (China has a state firewall that actively screens content)? If all are so equal why do only communist party members have only real power in such countries?