[Sagat]

The problem is that not everyone is making less progeny. Japanese and European populations may be in decline, but African, Asian, Arabic, and Hispanic ones are growing at a brisk pace.

So yes, it's pretty bad for some people to limit births. You are essentially diminishing your influence and putting yourself at risk of being swallowed up by other cultures.

[duopixel]

Population growth rate is declining all over the world, but the effect is more pronounced in developed countries. As standard of living increases people tend to have less children.