It's because that's not how trendlines work and because nobody is treating it as a serious problem yet. If things don't work themselves out naturally, and low birthrates do become a serious problem, then the different governments in the world will make real effort to resolve it. One way or another, it will stabilize because that's how demographics works. Sure it will take decades, but that doesn't matter much in the grand scheme of things.
It will probably stabilize at some point, but in the intervening decades it will also likely reorder the balance of power throughout the international system.
It's because that's not how trendlines work and because nobody is treating it as a serious problem yet. If things don't work themselves out naturally, and low birthrates do become a serious problem, then the different governments in the world will make real effort to resolve it. One way or another, it will stabilize because that's how demographics works. Sure it will take decades, but that doesn't matter much in the grand scheme of things.
