It has reduced our reliance on evidence and reason. Believing in evidence and reason is great if you want to be a productive and happy human. \
But, with religion, you get to be right, even if you have no idea what is going on in real life. And, you can find fault with anybody who doesn't agree with you. In fact, since you are so good at believing an unchanging truth, you can judge everyone else as inferior because they rely on evidence and reason.