The economics of infrastructure actually improve for stable or shrinking populations because funding can shift from raw capacity buildout (extremely expensive)

The economics of infrastructure actually improve for stable or shrinking populations because funding can shift from raw capacity buildout (extremely expensive) to maintenance and value-add services (profitable). Observe that the best infrastructure in the world is in nations with slow population growth, like Western Europe, Japan, and more recently the U.S. and China. Whereas nations with very high population growth struggle to deliver capacity for even basic needs like clean water or paved roads.