I think a lot of the disagreement in the comments here comes down to different ideas wrt the definition of overpopulation. When I talk about overpopulation, I talk about a human population that reaches the point where it's detrimental to quality of life for all beings on earth. Sure, we can sustain population growth for a long time by continuing to destroy more and more of our natural resources and wantonly disregarding the existence of all other life on this planet (and ultimately, our own), but can anyone who cares about the whole of the planet really look at that and consider it a net positive? In my mind, an anthropocentric perspective is as misguided as a purely misanthropic one, and is certainly more evidently virulent.