What's the clash? Is the claim that China lacks the notion of copyright, or that they don't care about the rule of law?

No, they have that. It's just not universally applied, or rather with 'some flexibility' instead :-)

It remains to be seen how much 'pull' FFmpeg has against the 'push' of Rockchip.

Not a fan of the CCP, but GH in general has a big problem with users not understanding and respecting licensing and passing off others' code as their own, sometimems unintentionally, often not.