I lived in Southern California for 8 years and I'd say that Orange County and parts of LA are at least as religious as Southwest Ohio where I now live, maybe more.
It's a different kind of religion, a different vibe, but there's not less of it. There's also a ton of new agey stuff in California that is no more rational or secular than old school religion, just different.
Boston may legitimately be less religious and less superstitious, but I'd be surprised if it was by a lot. Again, the religion is just different. There's a lot of Judaism, mainline Protestantism, and Catholicism up there vs. evangelical Christian and new agey stuff elsewhere.
So it's an issue of fundamentalism, maybe. Those areas like LA and Boston might be as religious in many ways as rust/bible belt places, depending on the metric, but they fundamentally are not confusing a day old zygote with a developed fetus, insisting the earth is literally 6000 years old and dismissing the idea we came from 'monkeys', they don't have issues with homosexualty to the same extent and maybe even belong to a church that is fine with it, etc etc.
It's a different kind of religion, a different vibe, but there's not less of it. There's also a ton of new agey stuff in California that is no more rational or secular than old school religion, just different.
Boston may legitimately be less religious and less superstitious, but I'd be surprised if it was by a lot. Again, the religion is just different. There's a lot of Judaism, mainline Protestantism, and Catholicism up there vs. evangelical Christian and new agey stuff elsewhere.