This isn't China's problem - it's a human problem[1].
This is why the first step in many first aid classes is for the care giver to identify one person among bystanders and instruct that person to call emergency services. Not "somebody call 911" because it's possible that nobody will - but "you, call 911. Do it now".
Also, if you read the article, it mentioned Kitty Genovese, and how the tale was likely apocryphal. That being said, the issue isn't that there is a bystander effect, but why in China it seems like the bystander effect is higher than in other nations.
There is obviously a lot of selection bias here...
I guess that's the part I really question - I don't see anything to support that it's higher in China than anywhere else.