The scope of what I'm talking about is bigger than yours. Cities are more efficient, and we need to move more people into them (not just the ones that are big r

The scope of what I'm talking about is bigger than yours. Cities are more efficient, and we need to move more people into them (not just the ones that are big right now, just to cities in general) to give ourselves a better shot at keeping our planet habitable in the long run. To your second point - degradation of infrastructure is not an issues with cities, it's an issue with management and investment. On a practical level, with additional people should come additional industry and tax revenue which should in turn allow metropolitan areas to keep pace infra-wise.