If everyone thinks that government will take care of them when they are old, they will prefer spending time on "self actualization" (whatever that means) instead of the boring dull work of raising kids.

Boring, dull, expensive and risky. We need to incentivize people to do it, not just give them vaguely nationalistic reasons to do so.

Pretty much the only people holding up births in the US is young people who accidentally got banged up. That demographic has only been shrinking as access to contraceptives and education goes up.

We don’t want to remove privileges from people, we want to add on incentives. Currently, there’s a million and one incentives not to have kids.

Not for the young people, no. Besides, countries like the US have made elder care a cash cow. We don’t actually want young people to care for the old, because we can’t bleed them dry that way.