What's the status of the GPL under Chinese law? Because maybe they're not required to honor it. IIRC, the GPL was written in the context of certain Western legal systems and depends on certain characteristics of those systems.
Even in a Western country, there's probably situations "give back" requirements become unenforceable (e.g. the copyright on the code runs out).
Yeah, the PRC is basically disregarding that, and yes, the Courts of WTO members are empowered under the TRIPS agreement to provide relief to the copyright holders. Start with Article 42 and work your way up. Chinese law doesn’t even enter into it, and under their political system, is explicitly “rules for thee but not for me” given that the CCP sits above the government and the law.
As such, even if there might specific incompatible provisions in GPL, the nature of the license should be enforceable only if they cared.
Though, to be honest, even in US and the "West", we haven't seen many cases where non-copyright-owner was able to score many GPL wins.
Not honoring the GPL very, very far down the list of moral wrongs, and certainly isn't in the "morally repugnant" category.