are people really not having enough kids in the west? I know Japans situation but I'm not current on worldwide fertility rate.

It's a problem everywhere except sub-Saharan Africa and even then it will be a problem by 2080. China is majorly fucked from it. The US survives due to Immigrants. Also anytime in the last 50 years that the UN or other organizations did projection on future fertility rates, they overestimated it. So expect any estimate you look up today to be similarly rosy in it's prediction.