I'd say there are limits to this. Honest belief and following religion will provide experiences to back up any religion to a point. It's then a balancing act to see if reality matches the experiences and teachings. If it doesn't, people leave or become strict and angry.
Beyond those kind of experiences, there are the experiences of the mystic. It's fair to say though, that then the idea of God becomes less meaningful and on that point comparisons to the straight-up atheists can sometimes be unavoidable while at the same time finding meaning in the deeper writings within religions.
What's difficult is that I have seen how constant exposure to an idea like a specific religious belief can influence the "reality" of what the subconscious mind provides to your conscious awareness as experience.
If I constantly exposed myself to some idea about reality or God, as a wild example, lets say I wanted to believe God was a dragon. I could immerse myself in dragon lore, dragon images, songs about dragons, and my subconscious mind would pick up on this, create a spiritual experience which feels convincingly real which I had no conscious involvement in creating.
The subconscious mind is capable of creating these spiritual/mystical experiences without your conscious control or knowledge.
So you have this experience, it seems very real to you. It happens entirely independent of your conscious thought or awareness. Why shouldn't you believe some outside force or deity is sending you a message? Really you have no way of knowing they are not.
My subconscious mind will create a dragon, one I've never thought of or imagined consciously before. Provide a profound revelation that suddenly makes all the sense in the world to me. Will speak to me, guide me independent of any conscious thought. Know more about the world than I'm consciously aware of.
It seems to me the reality is that we are finding ways to tap into our own subconscious mind not some cosmic deity sending requests to be worshiped.