In my opinion, the world is under managed. For instance, the urban areas are more populated than rural areas therefore straining the already scarce resources. The various governments should depopulate the urban areas by improving on their infrastructural strategies so that the resources can be properly managed.
Why is this an either or question? Could be both or could be neither. I would say neither. Overpopulation will fix it's self and each person should be free to manage their own life without some elitist know it all telling them what to do.