I don't judge him for taking shrooms and exploring whatever he has of a spiritual side. But I think the video was irresponsible because he heavily implied that ALL people with mental health issues should also explore this path. Shrooms and other psychedelics are not for everyone. There are severely emotionally damaged people who watch him who should have nothing to do with it. Perhaps they are not ready for it and possibly never will be. Prince Harry rightly got criticised for advocating Ayahuasca to a large audience.
He just advocated taking shrooms (admittedly an illegal substance in both his and many other countries) and not everyone has the money (or in his case a man who paid for the trip!) to go to a legal and therapeutic setting and experience it safely. An illegal substance can only be obtained illegally. Not that he cares as he's been taking substances and visiting prostitutes for years, but his viewers are known for being vulnerable, especially upon suggestions from him.
Yet another reason why he's not suited for "full-time activism" paid for by this community. The video was probably best kept private or thrown on his Random Cedars channel. But the views are more important to him.