If the root problem is population growth, how do you even begin to solve it? Even if population control measures were not an inherently unsavory social idea, economically it is extremely difficult to justify as well. I understand the orthodoxy of growth-economics and I'm not asserting that; rather, I'm pointing to the fact that if we were to somehow limit population growth to zero percent, then for the next half century or so the demographics would tilt heavily to the aged... meaning a smaller number of young people must work to generate wealth for a larger number (relatively speaking) of elderly. This kind of demographic imbalance is already considered an impending disaster for social security in the US, due to the baby-boomers entering retirement.
I can't even begin to imagine how you can address the problem of population growth in a proactive way, even if all the decision-makers had a systems level understanding of the problem - much less in our global society in which growth economics is the only proven working model for wealth creation.