Well, yes, until you actually think it through, and realise that this also means your population is aging... Basically, you have a bunch of old people around,

Well, yes, until you actually think it through, and realise that this also means your population is aging... Basically, you have a bunch of old people around, and nobody to support them, or fuel the society. And after a certain point, you can't reverse it, and you no longer have a viable society.