I think he just said he personally wasn't a fan and made a recommendation based on his own opinion. What's so wrong with that?

There are a lot of reasons why someone would prefer classic plant based psychedelics beyond the fallacy you point out. For one, almost anyone can cultivate them easily at home and doesn't require a huge initial investment or in depth knowledge of chemistry or a lab, all of which is extremely cost prohibitive for just one person who isn't planning on marketing the product.

I understand the fallacy, after all cyanide occurs naturally but it will kill you. It's just that there are other considerations as to why someone would say this.