> It befuddles me to see people relating this to external motivations, not a genuine concern for safety.
It doesn't befuddle me. China has a bit of a history of using safety regulations as a pretext for political and trade retaliation. China and the US are currently in a tariff war, and Boeing airplanes happen to be one of the US's biggest exports to China. While the FAA might not be perfectly independent, I'm pretty sure it's more politically independent than most Chinese government institutions. I'm actually surprised they didn't take an action like this sooner.
Here's a recent article that outlines some other examples of China using safety regulations to retaliate:
https://www.nytimes.com/aponline/2019/03/06/world/asia/ap-as...
> China said Wednesday that it is blocking some imports of the agricultural product canola from Canada because of fears of insect infestation.
> The move, which comes amid heightened tensions over Canada's arrest of a Chinese tech executive, is seen by some as a new tactic to seek leverage over Ottawa....
> [The foreign ministry spokesman] cited "harmful organisms" that he did not identify further, and said China's government "needs to protect the health and safety of its own people."...
> Canadian Agriculture Minister Marie-Claude Bibeau said in a statement that the Canadian Food Inspection Agency conducted investigations after China issued notices of non-compliance on canola seed imports, including nine since January. She said the agency had not identified any pests or bacteria of concern....
> China, whose rapid growth has made it an important market for many countries, has a history of using commercial retaliation against those at odds with Beijing.
> The most recent high-profile target was South Korean retailer Lotte, which sold land to the Seoul government for a U.S. anti-missile system opposed by Beijing. Authorities closed most of the company's 99 supermarkets and other outlets — often alleging safety violations — and a theme park project.
> China suspended a trade deal with Norway and restricted imports of Norwegian salmon after the Nobel Peace Prize was awarded to Chinese political prisoner Liu Xiaobo in 2010. It stopped buying fruit from the Philippines during a dispute over territory in the South China Sea. Britain and other countries also faced retaliation over meetings with Tibetan spiritual leader the Dalai Lama, considered a dangerous separatist by Beijing.