Countries which are simultaneously highly developed and not incentivizing child birth have low birth rates.
That is literally the entirety of the developed world. China as well is/will be now experiencing a rapid population decline as its birth rate drops drastically. The only developed countries with anything close to a sustainable population growth are those that have a lot of immigration, but that isn’t a viable fix forever (at some point the countries that are sources of immigrants will become developed themselves and have the same problems), and typically only first generation immigrants have more children than natives.
That is literally the entirety of the developed world. China as well is/will be now experiencing a rapid population decline as its birth rate drops drastically. The only developed countries with anything close to a sustainable population growth are those that have a lot of immigration, but that isn’t a viable fix forever (at some point the countries that are sources of immigrants will become developed themselves and have the same problems), and typically only first generation immigrants have more children than natives.