I didn't make your posts.
" Civilisations have risen, collapsed, and been replaced throughout human history. ...Demographic decline is one (of many) causes of civilisational collapse."
If by civilization you mean the authoritarian ordering of the world, regardless of extent, sure. The ordering changes. I only consider freedom civil, not authoritarian ordering.
In no way do I support the idea that the purpose of the gift of life is to support demographic considerations to protect anyone's world order. I'll give the gift of life simply so they can enjoy it, as I have. I'm not interested in creating folks, so they can staff armies, do my laundry, or take care of other people.
No ... I to the whole gamut of human interpersonal relationships ... government is only a small part of that.