It is and isn't. I grew up in China and I think the Chinese government is overacting to this NBA statement. If the Chinese fans decide to boycott NBA that's their choice and rights, but the government should not ban NBA in China.
At the same time, I am frustrated to see so much misconception and lack of empathy in the discussions here. The territorial integrity of China has a very important place in the minds of many Chinese citizens if not all given the recent 100 years of Chinese history. HK is globally recognized as part of China but yet we have seen all western media's efforts to spread anti-HK police sentiment and turn a blind eye on the violent activities carried out by so-called protestors.
I've lived in the US for over a decade. Before coming here, I had no idea how sensitive racial comments are. Over time I learned about the history and never made a racial joke in public or private occasions. It's not the best analogy, but I want to point out that Morey's HK tweet is out of line and doesn't deserve NBA's endorsement.