I’m glad you posted this. It was previously posted but I couldn’t remember the title for a search.
With all the recent blah, blah, blah about how the world will be so overpopulated we will all be eating only one small ration of soylent green a day this article postulates quite the opposite that we may experience a population crash.
An impending population inversion and crash (more elderly than young, then rapidly decreasing total population) is the single greatest threat facing humanity, but no one knows or cares.
Natural behavior shifts back to equilibrium. High rates of population growth fall, overshoot equilibrium for a while, then reapproach it from the other direction. Eventually, everything settled down at a stable balance, and the doomday criers (on both sides) end up with egg on their faces.