I always laugh when people tell me I use too much gasoline, or too much electricity. Many of these same people have kids, sometimes more than one, sometimes more than two.
The environmental damage I do will add up over my lifetime, and then it will stop growing at my own demise. Those other folks with kids are leaving a perpetuity of environmental damage. Even if they personally do one tenth the damage I do in their lifetimes, they are arranging for the damage to continue forever. The damage they are responsible for ultimately will be far more than my little contribution.
I think our planet would be much better of with a stable population of about 500 million. Finally, open spaces, room for genuinely wild species to thrive, less trash everywhere….