I think there is a switch and that is called incentives. We can see these tactics working at least on Japan. If China government starts providing huge incentive

I think there is a switch and that is called incentives. We can see these tactics working at least on Japan. If China government starts providing huge incentives, tax breaks I think couple will think about multiple children. The only problem of China is they can't rely on migrants like west because they may still want cheap labors for manufacturing. And Japan has separate culture problems with migrants.