It's been a while since this was updated (2014), but it indicates that over 50% of people consider religion "very important" in their life. Only 11% said religion was "not at all important."

So while you could imagine a society where 80% of people believe they aren't religious at all, the United States at least does not appear anywhere near that number.

https://www.pewforum.org/religious-landscape-study/importanc...

Is this website primarily polling Americans?

(You’re probably right anyways - there’s a reason I put ‘theoretically’ at the beginning of my first post)