Just be honest and admit that this possible solution (fewer kids!) conflicts with your ideology or your reader’s
The planet’s population has doubled in my lifetime alone, and I may see it double again, and it could be pure coincidence that all the warning signs clearly track the human population (CO2 levels, sea temperature etc etc) but maybe, just maybe, there is some causation there...?
We could all have nice things if, a few billion people ago, everyone had decided to reproduce at replenishment rate only.