Why aren't more people sounding the alarm? Even homogeneous first world nations with little merchant influence are dropping below replacement rates. It doesn't matter where, Asia, Europe, the Americas, practically any country that isn't a complete shithole either has a low birthrate or is in rapid decline. 

Poland for fuck sake has a rate lower than Japan, despite being very traditional and religious. China's birthrate is now equal to Canada's.

Countries that incentivize having birth still are dropping below replacement. Realistically, what else can be done? 

https://en.wikipedia.org/wiki/List_of_sovereign_states_and_dependencies_by_total_fertility_rate