Due to the specific ISP environment in China (massive NAT abuse, very limited public IP access, ISP actively dropping anything that does not look like HTTPS to ensure QoS), any P2P based protocol in China is generally unusuable. They are not blocked per se, but they are mostly non-existent.

Yes, I know BitTorrent network in China is huge thanks to the weak DMCA law enforcement towards individuals, but having no practical legal consideration does not mean it's enjoyable to use.