It very much is not.
The notion of people working for their selfish interests in a way that fosters cooperation and improvement on a larger scale gets treated to caricature interpretation often, but under that, there is a lot of evidence for it. Go ahead and describe a contrary viewpoint.
The inability of free market capitalism to regulate its own externalities doesn’t really plead in its favour either but I can’t say other systems have fared better there.
Anyway, I would hazard that most people in the world don’t work strictly for their selfish interests anyway but rather for a mix of their family, community while trying to apply their own moral to the best of their ability to foster a better world. Therefore reducing free market economies to selfishness on an individual level seems misguided.
While somehow trendy amongst part of the American population nowadays, the Randian idea of selfishness being for the best is not actually supported by much.
Seriously, what are you talking about?
To get back to my original point, I think modern China is actually pretty far from 'greed is good'.
It's an autocratic country where the central party has a tight leash on the economy and which doesn't hesitate to make CEOs disappear when they get too rich and powerful. Population movement is strictly controlled and central planning is very much alive and kicking in the more rural part of the country.
Even the housing market bubble was propped by state owned companies with state owned banks money which is why it's not exploding spectacularly.
Viewing China has a free market economy is a mistake. It's a mixed socialist market economy and under Xi that means a lot of socialism with a dash of free market.
That said gov’t can throw billionaires under the bus and use elements of the state to prop the system up may look nicer - but the average person still ends up losing/paying. We’ll see in a decade what that really looks like eh?