I mean these are well documented points borne out by history - when birth rates collapse empires collapse with them. And I don't think there is a clean solution to the birth rate being down - if there was then everybody would be doing it. It's a problem we see all around the globe because (my theory) is that advanced society is just structurally not geared towards high birth rates. We're all atomized, just "economical units" in the eyes of the system - there are no third places anymore, personal entertainment is more engrossing than ever, etc. I'm a pessimist on this but I think short of a true religious revival, low birth rates are a permanent fixture of a sufficiently prosperous society (the exception being extremely religious communities).

So if you proceed from these two assumptions - that low birth rates cause collapse, and low birth rates are a permanent fixture of developed society - the choice basically becomes to resign yourself to collapse, or to try and fix the problem in some way or another. Incentive-based fixes like tax cuts for parents, etc, don't seem to work. The only successful solution people have found for this issue seems to be immigration, which simply offsets the low birth rates.

This is also to say nothing of the fact that, for instance, immigrants found successful companies at a much higher rate than native born Americans.

I'm not saying there are no problems with immigration. There are definitely problems with immigration and there always have been. See Gangs of New York, for instance. But when the choice is between immigration and long-term demographic collapse, immigration seems to be the preferable choice.

Also, I'd honestly ask Claude about this. This is just my understanding but I think Claude or whatever would give you a better picture.