I have experienced the absolute fury when bringing up overpopulation. Like religion, it's one of those deep-seated superstitions that people ought to reproduce as they like unimpeded. Back when half of your children died from infectious disease and you needed to breed your own farmhands, large families might have been necessary but they aren't now. The same kind of prosaic thinking goes into the anti-choice campaign, that the world needs every human it can get or the fundagelical drive to have as many children as possible in some kind of deluded idea that they can outbreed the heathens and brown people.
In many countries, birth control is not available at all, and men do not wish to use it. In India, the government tried a campaign to reduce their out of control population by trading something useful to each man willing to get a vasectomy: a bucket. There were some takers but not many. As birth control through the male is far far easier than through females, it only makes sense to deal with the issue through that route. But our old superstitions rear their heads again. Men are not considered virile if they can't impregnate lots of females. Caveman thinking.
We have not progressed very far in our beliefs so now we are in a perilous situation. Overpopulation of humans mean animals and ecosystems are pushed out or stripped. We need to start some new way of thinking where people are not isolated and full of harmful superstitions. Some kind of community building and what it means to be a good member of that community would help. And #1 should be the development of 100% effective, easy-to-use birth control. We have all these technological breakthroughs and yet can't manage that? Bollocks. That would be a true gift to the world but there has to be the will to make it and to accept it.
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