AFAIK Chinese piracy is a different culture, its mostly done on private/secret forums not with the same public torrent/archive methods we use. Also I'm confident hosting a website inside China is no simple matter given the regulations, certainly it would be trivial for authorities to notice the foreign traffic.

Which leads to the final point, the firewall is also to prevent exactly this.

The CPC isn't going to act on a shared principle of fuck the west here, on the contrary they'd see hosting western piracy content as a potential threat given it bypasses the firewall.