Censoring the internet in China prevents certain ideas from being published in any form. In practice most Chinese internet users visit domestic websites and any censoring of content is a bigger policy blocking that idea, such as academic information that does not directly affect most daily users.
There is also pro-government supporters who will target domestic critics even when it is within their rights in China. These are like patriotic Trolls that will break domestic laws.
What kind of ideas are disallowed within China?
For daily internet users in China, these complex issues aren’t an immediate concern.