Huge cities disappearing as remote working, automation, rising sea levels and mass migrations make most of them pointless.
Lots of civil unrest, mass migrations, new plagues and wars as the globalized economy collapses and disappointed voters choose new kinds of populism to save them.
Rich people moving to the few lucky countries that won on the global warming and now try to isolate. Everybody else fight for scraps.
Eventually population adjusts and stabilizes on much lower level and reproduction rates grow again as repopulation starts.