There's definitely a misconception in the west in this regard. I've lived 2 years in China, and I was surprised to learn how much freedom the common Chinese citizen has, in some instances even more compared to westerners.

In specific to this post, there is a lot of "dissident" cultural productions freely available. To just take an example of a recent movie that comes to my mind right now: "Let The Bullets Fly", a comedy-action where a Robin Hood-type thief tries to rob a village ruled by a criminal ruthless kingpin, supported by a corrupt governor. (spoiler alert) at the end, the hero organizes a militia, distributes guns to the entire village and takes over the village. It is absolutely clear this is a satire over current Chinese politics affairs, yet it was released as a major movie in cinemas everywhere.

Figures like Ai Weiwei only perpetuate this misunderstanding that China is some kind of North Korea, when in reality there's already a lot of "challenging" going on.