There are at least three different claims here that I'd like to unpack:

1) "If you really have to pick a belief system to put your faith in, you can do much worse than traditional religion." Now, I'm a lifelong atheist, and atheism is one of the few things I never changed my mind on, but I came to the conclusion that this is probably true: at the very least, traditional religion is a stable belief system that won't destroy your life.

2) "A lot of people who aren't traditionally religious, actually follow some random bullshit creed that's much worse than religion." I agree with this, there is a genuine human need religion fulfills and many might want to "fill the void" with subpar alternatives.

3) "If you are an atheist, then you necessarily fall into case (2)." Which is blatantly false, as the existence of millions of perfectly well-adjusted and functioning atheists shows.

>at the very least, traditional religion is a stable belief system that won't destroy your life.

That might be true in liberal western democracies, but there are many parts of the world where your particular choice of religion may well destroy your life or straight up get you killed, if the people behind the next coup don't share your beliefs. Even in the west you might hinder your own success if you pick a non-majority system.

To be clear, I’m not asserting that (3) is the case. I’m just saying that as a practical matter it’s a small number and a lot of people that abandon traditional religion fall into your (2).

Believing religious woo doesn't preclude one from believing non-religious woo. If anything, believing religious woo seems correlated with believing non-religious woo: https://www.economist.com/graphic-detail/2021/07/27/what-dri...

Evidence that such a correlation exists for “white evangelicals” in the US tells us nothing about whether it exists for religious people in general - including religious Americans from other racial/religious backgrounds, and non-Americans. Your observation might not be true for religion at all, only for a very specific type of it

The idea that religious people don't have bullshit creeds outside their religion is a false one.

Religious people in America act religious on Sunday and like ruthless, immoral "greed is good" capitalists on Monday, flexibly switching ideologies for their convenience.

You're describing someone with a ruthless flexible ideology. A truly religious person would apply the principles of their religion during the week too.