Every normie who blames economic conditions for low birth rates or anything related to economics needs to be confronted with questions about which country has the best economic conditions? And then you look up the birth rate. Chances are, the birth rate will be low in spite of the great economic conditions.
Repeat the process if they try to name a different country.
Also, there is never going to be the perfect economic conditions that will raise the birth rate. Because that is not the problem.