Earlier quoted context omitted.
Whether it's policy, technology, or medicine (I don't quite understand why medicine would reduce the metric we care about, number of surviving children) doesn't matter. There may be a solution a nation could take, but immigration enables it (or rather, its economy) to persist, without addressing the falling birth rates, at the price of slowly giving way to a new, immigrant population.
>at the price of slowly giving way to a new, immigrant population. What's wrong with immigrants? My father was an immigrant. My mother's parents were immigrants. Babies are "immigrants" from someone's womb. I'd note that all humans are immigrants to every place except Africa. Further, I'd ask why you care where the person (or their parents) who installs the side view mirror on your car at the factory comes from? What…
Not to mention it is in the interest of any organism, any living being, to produce descendants, so any policy that promises long-term sub-replacement fertility is dangerous from that point of view alone. It frankly boggles the mind this is something I have to explain.