The government, media & academic narrative since the 60s to the West was that there were too many of us. We assimilated that into our culture, while most of the rest of the world just kept on growing.

Now we're told they 'got it wrong' and we aren't having enough kids, and we need unlimited non-Whites to top us up.

I don't think that's a mistake.

They look for a common factor on low birth rate countries. I wonder how many of them were significantly culturally affected by WW2?

Broad-civilizational demoralisation.

https://www.youtube.com/watch?v=A6s8QlIGanA