> Going by this, I also think that you may have the correlation wrong. If the study is correct (more generous welfare systems => less decrease in birth rates),

> Going by this, I also think that you may have the correlation wrong. If the study is correct (more generous welfare systems => less decrease in birth rates), that seems like it would mean that people who can afford it will keep having kids. It does not matter direction what the relationship is, only that it exists at the family level and so family-level correlations are non-causal for the effect of coronavirus as claimed by OP. We should be equally skeptical for the same reason if the result had instead came out as "kids during coronavirus have 10 higher IQ points because their parents played with them more thanks to remote working and subsidies"; there is no reason to believe that changes in childbearing during coronavirus has been, in any place, exogenous and randomized, and we know that pretty much all of these relationships are partially to completely confounded, thanks to studies which do include family controls (like all the Scandinavian population registry studies which exploit siblings). The burden of proof is on anyone who wants to argue that their correlation is the one special snowflake immune to this general trend, and should be taken at 100% face value.