"On the brink of being unable to maintain social functions"? Come on, now. We have more people then ever before on this planet, and we've been maintaining social functions for centuries with much smaller populations thean we have now. Get a grip.
Also, if you cannot understand that the planet has limited and finite resources and the impending threat to significant swathes of humanity is that we're running out of food production capabilities and clean water, and that the effects of that are going to be nothing short of devastating, a quick Google will give you tons of reading materials to give you a new perspective. Start with a book called Ten Billion, then come back and let us know if you still think population decrease is the thing to be worried about right now.