My point was more that there is a huge genetic selection event ongoing in the developed world. The genetic fitness landscape has changed as a result of modernit

My point was more that there is a huge genetic selection event ongoing in the developed world. The genetic fitness landscape has changed as a result of modernity and people who somehow manage to have a bunch of kids despite living in developed countries carry the genes that are currently being selected for. Regarding religious people though: religiosity is a heritable trait. Not perfectly heritable, but heritable nonetheless. So if religious people have above replacement fertility and secular people don't, then the religiosity of the population as a whole should shift upward over time. It might take a long time, but that would seem to be the implication.