it's not. China is looking at a demographic collapse in the next few years that upends their running economic model and makes any future projections based on past history suspect. One of the ways out of demographic collapse is immigration, but somehow I don't see China's equivalent of US's Mexico/LatAM coming out of the global geopolitical woodwork. Immigration is simply not in China's DNA. Outside of immigration, no amount of "scientific management" or "good policy" will make 18-30 year-olds appear magically over the course of 5-10 years. Unless my understanding of biology is wrong and dolphins could sprout legs and walk on land, usually it takes 18-30 years.

I'm willing to change my mind. What sort of an ace in its hole does china have to change this situation?

What does demographic collapse mean, specifically?

The one child policy is 40 years old, China has been 4-2-1 for like 20 years at least, and no collapse has happened. Now they're allowing 2 children.

What's the specific thing that will collapse and be bad? An oversized retiree generation dying just frees up pension cash.

The specific thing that will collapse is the economy.

When people retire there is a sudden shift from investment to liquidation. That's a driving factor for popping asset bubbles, and china is currently one huge asset bubble.

Like it or not (i personally dont), we are also living in a world where the central planners rely on consumption-driven economics, and there just isn't a chinese consumer market anymore due to demographics.

The multi-child family people are already retired, though, and long-retired at that. Them dying out means a shrinking population but also lower pension costs with no lost labor.

The working population has been steady-state at 1-child for 40 years followed by 2-child for the last few years.

I suppose there could be some demand loss due to fewer people demanding things, but.. there's a lot of room for additional demand in China. Plenty of people where running water is a last-20-years nice new thing.