China's problem is a universal problem. They're "communist" in name only. Their economy has capitalist demands for growth/metastasis, same as ours and most developed economies.
People want to have kids when they can expect those kids to live at minimum the same quality, and preferably better quality, than they themselves did and do. That just isn't the case anymore as the global economy has run out of massive new sectors for growth/metastasis and has begun eating itself. You can see this in all the entire sectors here merging into monopolies and duopolies. Constant merging isn't a business strategy, it's just trying to buy time in a failing economic model.
Capitalism has always been a long-term pyramid scheme to concentrate all the power/wealth/means/capital to a small owner class. The problem is, the con has run out of new places and ways to exploit people as you eventually can't squeeze more out of a fully exploited stone. No pensions, laughable pay, no future. Just expected to thanklessly generate capital for the owners in larger and larger quantities for the love of what? The nation trying to commoditize your entire life to profit the right people? Why would you bring another poor, desperate child to suffer such a world?
Now, in their desperation, these economies that lead their societies and governments around by the nose are desperately screaming "MORE LIVESTOCK TO EXPLOIT GOD DAMN IT!" because in lieu of not being able to squeeze any harder on existing capital batteries without being correctly told to 'get fucked,' that's all they have.
I firmly believe that is why the federalist society that runs our SCOTUS is trying to get abortion banned, as the most profitable capital batteries are desperate, poor ones. I also believe the intentional decline of our public education system is meant to address the same problem, if they can make the population stoooopid enough not to consider the lives the children of already struggling peasants would have.
This world is finite. Its resources finite. An economic model literally based on infinite continuous growth/metastasis or die is not compatible with the world as it is. In every sense, it is killing us, whether by climate change from without, and loss of actual personal meaning within, at least for the non-winning vast majority. The goal of global economics should have been to establish a sustainable population that could find equilibrium/homeostasis with our shared, COMMUNal environment we all rely on from one breath to the next. Not a lot of room for Super Yachts and private jets in such a world though...