More die of disease and other miseries. Your collabrative society isn't saving them now despite a hundred years of trying. Your collabrative society works in America and Europe, currently in many other arenas, but not in large parts of Africa nor in so many other places in the world.
Having said all I have to say on the subject, ma earth will rid us of millions if not billions in the not too distant future. This century? Maybe, maybe not, but in the grand scale of our few thousand years on this planet it's coming as the population explodes. By failing to voluntarily reduce our rapid population exapansion, we are dooming ourselves, or rather our children and/or grandchildren to the lives of the lemmings we so fondly talk about. Remember the adage, "Barbarism is only three missed meals away...." The water wars are currently under way, the food wars cannot be far behind.
The simple fact is for the few who see what's coming, there are dozens who are ignorant, foolish, or too selfish to curb their genitals and imagine that THEIR kid, maybe YOUR kid will save the world. The imagination may be a wonderful thing but in this case it is fatal. It would be simple to voluntarily reduce our numbers. As a species, we are not that smart.