It's true even if you don't take psychedelics. There's a tendency to confuse peak experiences (however that comes about) and awakening.
Bonnie Greewall, who wrote her PhD dissertation on specific form of spiritual emergence in the field of transpersonal psychology is one person who teaches this. She speaks of people who, having confused those peak experiences with "enlightenment", goes on trying to seek out greater and greater experiences. There is a kind of withdrawal effect that happens when the next big thing doesn't show up. This is in contrast to awakening, in which one is aware of true nature as awareness. This awareness is available in all states, whether blissful or wrathful, with or without psychedelics.
At the end of the day though, it's still about awareness, whether that is in the ceremony or in the ordinary life.
I think the psychedelics gives the kick out of the nest some people need. I know a lot of folks roll their eyes at some of the things being said in the article, but having participated in ceremonies and hanged out with the folks who go, they are not as far-fetched as you might think it is. Both the cringe-inducing quotes and the folks who roll their eyes are, I think, representative of the the spiritual miasma and dis-ease in modern society.
And since I got into some drama here the last time I said something like this, I'm going to try to write as clearly here: while there are some people who can answer what these peak experiences and these spiritual paths do for themselves as individuals, we as a human species and a race _as a whole_ still have not figured out the place and purpose of spirituality in modernity. Modernity was first the separation, and then the complete disassociation of spirituality. A Dagara medicine man friend of mine puts it, "there were the Keepers, the Breakers, and the Menders". The Keepers are traditionalists. The Breakers are modernists. The Menders are only emerging.
Modernity broke the traditional views, with some proponents seeing themselves as heroes for doing so. Although it isn't as if all traditional views were all that great, in the glee to toss everything out that smacked of traditional, we left a big gaping hole in our beings. We don't even have the language in modernity to speak of this without feeling cynical, or opening ourselves to being attacked for being superstitious.
This is the hole that traditional spirit medicines like Ayahuasca helps now -- despite, as the article says, it wasn't traditionally used that way. It just happens to be something a lot of us need, even if we don't always know we need it.
But since we don't have modern (or post-modern) language or framework to speak about spirituality in a coherent way ... well, let's just say we're all engaged in a grand discussion about that, groping together towards the answer. Ayahuasca is part of that ongoing groping we humans are doing.
Whatever we come up with, it's going to radically include both traditional and modern view, both rational -- and yes, irrational and transrational things about our world.