Well I wouldn't both-sides this one. 2020s population forecasting is better than 1960s forecasting, the latter was repudiated and the former is correctly modeling basically everything. Demographic decline really is happening and has reasonably well understood mechanisms.

I suppose I would separate out some of the more extreme predictions about demographic collapse in Russia or China. I'm not sure what to make of those or if they're similarly credible to other kinds of population forecasts.