> If using them results in this sort of thinking process, I think that I would be better off steering clear.

This is a normal sort of thinking process, psychedelic or not. Let's look at this sentence:

> ...so some plants and fungi are especially interested in enlisting our support. I think they have a consciousness...

Pollan is exploring a metaphor. The metaphor in question is "plants as people": plants are "interested" parties, plants "have a consciousness." He's using the metaphor to better understand how plants work. Anthropomorphization is a major feature of how humans understand their environments.

You'll note we use similar mental constructs with software, if you look closely at the language... Metaphor is the root of all abstract understanding.

Mushrooms definitely give you the feeling that everything around you has purpose and motive. The tree to your left isn't just a tree any more, it reminds you of a dragon, and you can determine its character, etc. You feel connected to things and can sense the "life" in everything. It doesn't mean you have to update your physical worldview. But the feeling is powerful, and is accompanied by some strong insights into your own life. Highly recommended, even without any spiritual inclinations.

fwiw, i've done a bunch of LSD and mushrooms and I think it sounds as stupid as you do.

That said the experience of a psychedelic trip feels completely impossible and indescribable on every level so I can understand how people reach for absurd metaphors to come to terms with the experience. It's a very difficult experience to integrate.