[gorjusborg]

If you see constant economic growth as a requirement of a functioning society (also a bit silly), a shrinking population is concerning because it suggests that demand will shrink with the size of the population.

Shrinking demand can lead to deflation, and deflation is bad.

I'm not saying all of this is well-reasoned, but I do think it is the level of thinking involved.

There are also the practical realities (e.g. health care) that could become unbalanced if age profiles look like an inverted pyramid (https://www.populationpyramid.net/world/2026/), but I doubt that most people are thinking that deeply about it.

[apothegm]

On the flip side, if you redistribute effectively, going from N people on the brink of survival to N/2 people living a moderately comfortable lifestyle is unlikely to decrease overall demand much. Its only if you’re keeping those N/2 people each at the same level of household income as the N people that demand halves.