You are correct, the “ghost city” claim is about a decade old and in the time since then good functioning cities developed incorporating those infrastructure and urban resources built previously.
Zhujiang New Town for example can house up to two million people (often moving out from the 7-10 million living in the old areas) and while I dislike the urban planing of it, it was once among the foremost called “ghost city” in propaganda, yet it is larger than most cities in most states of the US as example.
I also agree that having too many flats seems to not be that bad a problem to have. Especially when 2‰ of the US are unhoused - even though there are millions of empty flats.
The numbers will sink in the next 20 years for pretty much all “developed” OECD countries. Including the US, UK, France, Germany… yet how often do you personally write about that problem? When even people like professor Reich of Berkeley mention the 40(?) trillion $ wealth transfer due to shrinking population and that mostly to a small group of population with reduced demand for housing you seem to focus a lot on a country you are not living in.
Do I think China faces challenges? Surely. Do I think the capitalist market oriented parts of it will lead to problems that are integral to capitalist market systems? Sure. The CPC has much more power to act on it though. China is currently able to house its population much better than 30 years ago after the crisis of the fall of the Soviet Union. Germany’s capital is missing 600k affordable flats at the same time.
Lets see how things will play out, but similar articles were published every couple of months for the last 20 something years. That generates sentiment.