A lot of the insights most of us have on psychedelics can easily otherwise be obtained by reading a couple of pages of Schopenhauer, or hell even Hegel.
That's not "having an insight", that's reading a book and digesting a description of what could be an experience. I can describe you a roller coaster ride right up to the tensile strength of the steel alloy of the bolts of the track, but while you to some degree comprehend the rollercoaster, you have never, ever, taken the ride and experienced it.
An insight read about has almost none of the value of actually having the experience of the insight.
The difference is that between reading about love and being in love. People can write the most apt descriptions of love but none of it has any meaning compared to experiencing the real thing, in real time, in the exact way it manifests for you.
Books are a trap.
Schopenhauer must be good at giving literary head if you equate reading him with experiencing the real thing and saying the real thing has no significant greater value.
You can read the entire Judo method in an afternoon three times over, with pictures illustrating every step, but if you never once wore the Gi, stood woith your bare feet on the mat, facing a formidable opponent with nothing but what you've learned, being thrown, throwing and triumphing, you know nothing of REAL Judo.
If reading the Bible made you experience God Earth would be a paradise now with nothing but the most well intentioned people, but to quote a fighter of World War I: "After 2000 years of Mass, we've gotten as far as poison gas."
Books are shit - this from an author :D