All countries have censorship, none have freedom of speech. The class that controls speech is the class that controls the state. In capitalist countries, capitalists use dominance of the state and private media to disseminate ruling-class ideology. The same happens in socialist countries, only this time it's the working classes with domination over speech. "Freedom of speech" is generally a euphamism for allowing capital and money to dominate the speech of society. This is also why the Chinese population feels very positive about their own system of democracy:

The reason China has billionaires is because China does have private property, and a rapidly growing economy. What's important about China is that it is consistently the lower portion of society that's actually seeing the greatest gains:

This simply does not happen in capitalist countries, especially not in the last few years where private capital has been astronomically expanding. China's people-centric development has resulted in the strongest and most rapid rise in living conditions for working people in the modern world.

Jack Ma is an example of worker-rule in China. Jack Ma began undermining the socialist system and publicly advocating for reforms that would strengthen the autonomy of private capital. The CPC ruthlessly punished him for trying to undermine worker power, and stripped him of his speech. The same happens in reverse in capitalist countries, the state regularly strips working people of their right to protest and speak against capitalism. There is therefore no true free speech, and therefore it's important that the working classes control speech.