There are a lot of people in China, and most don't speak good English. Free exchange is thus already limited before we even get into censorship. The large number of people in China means they have the potential to create a new ecosystem. They just need to get a few of their own people to start it, and then let things grow. I don't know if they can pull it off, but they have enough people to at least make a good try at it.

Of course they can then censor it as desired.