The Chinese government isn't stupid. They do what they do because it works. Even the opposition agrees with this, hence the term
https://en.wikipedia.org/wiki/Chilling_effect
The website dedicated to the topic of the OP article is even called... http://chillingeffects.org/ (since renamed to https://lumendatabase.org/ )
Banning specific representations of an idea is a game of whack-a-mole. As soon as you ban one symbolic representation, a new one will be created.