> Meanwhile my religious-FAANG friend has 4 kids, lives in a community where everyone knows each other, lives much closer to family (intentional choice) and just overall sees his life, both the ups and the downs, as part of something purposeful and meaningful.

I am a full atheist, living in Switzerland. The community is strong, the neighborhood too and the city is a charm (Geneva). 3 kids, coding and spending my time contemplating humans at their best: having fun and getting on a higher ground. I don't have an answer regarding the bigger picture but I will surely think about it and get back to you.

EDIT As I wrote in another comment: confronting the truth (whatever the spirituality behind) in itself doesn't make someone unhappy, it's the sense of losing one's footing that does. In many ways, America was built along those lines.