Yeah, true. But I think the argument holds also for this utility function. There is something about your society that you like, else you would be somewhere els

Yeah, true. But I think the argument holds also for this utility function. There is something about your society that you like, else you would be somewhere else. And, bluntly, if your society doesn't make babies, today, then in 20-30 years time there won't be people brought up in this culture. Either your society will go into decline for lack of said people, or will rely on immigration (assuming it's attractive to expats), eg people with different values to your society's. It's not saying one society is better than another, only that if you think there is something good about your society (liberal rights? nukes? hell, maybe you're North Korean and like dictators!) then it takes babies to sustain it. The default is you will get people brought up with values of most populous societies, which may or may not align with yours.