It’s not that simple. To what living and health standards and level of freedom? At what environmental cost?
We had 3 billion at much lower standards of living in the 60s and the dire threats were combined with the “ZPG” movement of the time.
Higher standards of living require lots of energy. There is a strong correlation between a nation’s GDP and its energy consumption. In today’s world, it is hard to increase energy production, at least in the developed world. The developing world argues (with a lot of merit) “you got yours — who are you to deny us now?”