Is there hard evidence that this is bad? Resource depletion is among the highest risks to civilization. Seems straightforward that severe population decline should be desired, and voluntary refraining from reproduction should be welcome. (Please don't just extrapolate the trend till extinction. See http://xkcd.com/605/ . )
Is there convincing evidence that resource depletion is among the highest risks to civilization? Much of what I've seen shows the opposite: for example, China is a rising superpower largely because of their huge population. Having more people means more potential productivity, and that could lead to more prosperity. On the other hand, small countries with few people are usually able to accomplish little. Places with…
I agree with your point that, from a nationalist perspective, population size is basically nation size.