Overpopulation is not the cause of global warming. Most carbon is produced through the endless consumption of the economies of Europe and the US. It is not from places with high populations.
These talking points must be fought whenever and wherever they arise.
this actually isn’t completely accurate, early human civilization deforested huge regions and actually created deserts and mini ice ages from it. Industrialization upped the scale massively, but most human civilization has always been at odds with the ecosphere. There are exceptions where certain peoples lived in better harmony, but generally large scale settlement and agriculture is destructive no matter how it’s done.