What's the alternative though? Creating new humans purely to be able to have them work and pay for stuff for other existing humans? That doesn't seem a bit dystopian for you?

The problem I have with this logic is that it seems to assume a binary of the population either staying at least as high as it is or massively reducing. The idea that there's no middle ground where the population goes down slowly rather than massively spiking all at once feels like it needs much more justification rather than just assuming it.