I understand it's supposed to be an abstract concept, but this statement still doesn't make sense
Christian religions for example set a certain stage, create an atmosphere that puts people in a shared mental state. Meditative, perhaps. I can see (although never experienced myself) how that, if you let it "in", can lead to a "religious experience" / awakening of sorts.
Worst one was that one time I was in an American evangelical church, the type where there's lots of music and the like. But also weird behaviour; during the sermon, lots of people around me had their hand up and were whispering "jesus", it was eerie as fuck to be honest. That line of churches does a lot with altering brain states though, one article I read mentioned measuring brain waves and seeing them enter an "alpha" state, similar to hypnosis and making people very susceptive to suggestions. Another example is exorcisms, where people go - let themselves go? - into a state of dissociation, speaking in tongues and spasming. I kinda see that as letting their own inhibitions go and letting the impulses take over.
TL;DR not a scientist, just armchair theorizing and waffling.
It's not uncommon to forget one has taken psychedelics when one is having a powerful trip, and just telling yourself that it's chemically induced and will stop in a few hours doesn't necessarily help.
That's not to mention that while under the influence of psychedelics a single minute might seem like many lifetimes, or you could feel like you're in an infinite time loop and are never getting out, etc.