And that taboo is probably rooted in evolutionary psychology, people have a genetically driven tendency to criticize those who advocate having less children? So could there be an instinctual drive behind it?
https://www.flashpack.com/solo/relationships/dont-want-kids-...
Each American or European, whose food is grown thousands of km away, is plenty more only to make their salad. Can they be blamed for their Carbon Footprint^TM? I think we should blame the fossil fuel corporations which have turned us into fuel junkies
It's less true that a valid comparison should be "if not modern 21st Century life then hunter gather".
There's a middle ground more agrarian, less hunter, lifestyle that supported a large population in the past and can likely support a larger population than Victorian times if farming | mining switched across to renewables (electric | hydrogen) instead of fossil fuels - we've learnt a lot about efficiencies in the past century, it's a matter of application and less consumption now, certainly time for less greenhouse gas being released.