I know a number of former Christians who ended up that way after actually reading the Bible.
I think Penn (from Penn and Teller) tells a story about how that’s when he realized he was an atheist and it was BS.
Ive read the Bible from start to finish (including Numbers…fml). There are some wise fable-like, sage scriptures that could be valuable life advice. But it’s wildly inconsistent and paints a picture of a fickle, powerless, pathetic God. It becomes very obvious that none of the Bible is “the word of God”.
After reading it, it’s also obvious that most Christians (American Christians at least) haven’t read it.