Stanley, I need to look carefully at what looks like a fascinating article, but my suspicion is that the malign consequences of the birth dearth have been wildly exaggerated. I can certainly believe that it is true that we have never seen economic growth in a society with a shrinking population, but that is because such societies are very rare. Where they have occurred, the shrinking population is the product of a catastrophe from outside, war, for example, or disease. Catastrophes and economic growth do not normally go hand in hand (recovering from them is a different matter).
It might be more instructive to see what sort of correlation there is between the rate of population growth and economic development.
Of course, shrinking birth rates will cause some problems. Nevertheless – and maybe it’s because I come from a small crowded island – but I view the prospect of smaller populations with calm, contentment and, yes, enthusiasm for the greater legroom.