Earlier quoted context omitted.
having kids is, by default, right and moral.
You made that up. It’s very easy to think of circumstances where it would be very immoral because of all the suffering the children will have to endure.
Basically under no circumstances it will be immoral for the population at large to have kids because such moral norms will quickly cease to exist. Eather because it's bearers cease to exist or more likely because they move on to more suitable moral norms.
I say "more likely" because humans obviously didn't get extinct despite bringing kids into the world of suffering for about a million years.