Studies show that with improving living standards birth rates drop. There's the suggestion that we wont exceed 11 billion people (https://issuu.com/habsboys/docs/habs_geo_mag21-6th_issu/s/13472380)

Good news: its happening in developed countries already. South Korea's birth rate in 2020 was 0.84 kids per woman. In order to keep population stable you need 2 births per woman. I think there is an imminent collapse in demographics that will be coming within the next 20-30 years.

Developing nations still have higher population growth but eventually itll all even out.

While I agree with the sentiment, I don't see a way to do it.

It's just very unrealistic... Look at China's one child policy and all the other countries where decades of contraceptive push has only minor success.

Thankfully you don't seem like the type who could actually inspire or convince anyone to get behind your ridiculous ideas.