The word "ineffable" is a common one in the literature that documents altered states of consciousness for good reasons. You must be an initiate. Once you've dabbled in spiritual contemplation, breathwork, or psychedelic journeys, you know what the figurative language points to and it's no longer puzzling why the seemingly separate groups you mentioned come together.

I'm not asking why these different groups come together, it's not very difficult to understand. The confusing part for me is deciphering which comments and arguments come from which school of thought. That seems to be nearly impossible unless you have personal experience with this topic, and I don't due to it being such an impenetrable topic.