I’m no expert either but I don’t think population control is the only effective way, because if you think, if these poorer places which are pretty much surviving by heavy industrial means all decided to skip one or two generations, this is probably around 20-32years, I highly doubt that emissions in this time would drop. And should their governments adopt more proactive emission control methods during this time, the number of children and young people/adults most likely won’t impact the intended outcome. In fact I’m more inclined to say that the newer/younger generations would have a much more positive outlook in regards to climate change missions since they can be educated very early on, and wouldn’t be subject to drastic changes like the older generations which would be much harder to overcome financially. The best form of control imo is education, teaching young people the drastic effects and the way the earth is. A bit of anecdotal “evidence” from a quick conversation with someone twice my age about electric vehicles:”hey would you consider buying an electric car?… nah no way, not for me that… why is that then?… well I prefer combustion engines, I’ve grew up with them all my life etc and the range is ridiculous, 200mi, what if I want to go on a holiday? What about work?” This little example is intended to show that despite the obvious positive change an e-car makes, this modern middle aged man refuses to make this change most likely because he isn’t educated on the matter, where as I am going to snap up an ecar at the earliest opportunity because it’s a step in the right direction and I am willing to make that change. Change is hard when you’ve done the same stuff all your life, young people are the key.

So in short, population control described above imo wouldn’t make much of a difference to the global climate mission, educating the next generations would have a much bigger impact since they won’t be going through a change, what we want to happen would be the norm for them. The adults you would be stopping having children will continue to carry on just as they are with very little awareness and willing to alter of the consequences of their current actions.