It worked horribly. Humans love sex. They also love consumption and material goods. You are not going to convince people in developed nations to cut back their consumption. And you are not going to convince people in developing nations that they will never have the lifestyle of the developed nations. In addition, in a democracy, attempting to try to do those things will be political suicide. People will happily tell pollsters that they want to combat climate change, but the minute it affects them (for example rising fuel prices), they will be out in the streets attempting to throw the politicians out of office (see the yellow vest protest in France).
For overpopulation, the solution literally turned out to be a pill. Once women had access to safe, cheap, reliable birth control, population growth leveled off.
Either tech will save us, or we are doomed.