Alternatively you can also meditate/pray your way to similar states as the ones psychedelics induce. It takes a ton of practice, but I was able to generate very notable open-eyed hallucinations after just 2 years of low-intensity meditative practice (roughly equivalent to 120ug of LSD).
It is totally believable that a true religious zealot would be able to achieve much, much more with decades of practice.
Ram Dass told the story about how he visited the guru Neem Karoli Baba (AKA Maharaj-ji) and gave him a bunch of LSD, which supposedly had no effect on the guru because he was already having open-eye hallucinations from his meditation.
In your experience, how common is this? I must know at least thirty people that have meditated for over 15 years, and none have mentioned open-eyed hallucinations.
It is totally believable that a true religious zealot would be able to achieve much, much more with decades of practice.