I think it depends on the person. I was scared off psychodelics for a long time after a bad LSD trip (I unwittingly took too much, and was in an inappropriate, overstimulating environment). However recently me and some friends ate four toadstools each, they all had mild experiences, they were just a bit stoned and giggly.
I on the other hand forgot who I was and went on an intense, very visual, six hour long trip into what at the time I thought was the spirit world, a secret living world behind all inanimate surfaces, even though (when not tripping) I'm strictly an atheist with no spiritual beliefs. Absolute ego and identity loss, everything was writhing and responsive and alive, eyes and psychodelic patterning were emerging from everywhere. It was quite over the top, but very positive, everything seemed to be a wonderful complex joke that was slowing unfolding. Much stronger than LSD as I have ever known it, more positive and much more visual.
But there may have been active ingredients other than psilocin in the toadstools.