Doing it alone, or with some burnt out druggie friend is not likely to work except by pure accident, and making it worse is just as likely.
But no, they're not.
I once had a life-saving surgery, which was a relatively new procedure and that I felt could sort of reasonably be called a "miracle surgery" (to make an analogy to your comment).
The surgery required all sorts of right settings- a sanitary operating room with lots of light and climate control and space for multiple medical staff to be in the right positions and complex after-care that involved medications, IVs, monitoring of vitals in a specific setting.
I would never say "since my surgery required the right setting, it's probably because it wasn't a miracle surgery". Nor even, "since my surgery required additional medications..." or "since my surgery required required subsequent physical therapy" or anything else.
Lots of treatments for lots of conditions are going to involve a mixture of many modes of treatment, or only be successful if multiple independent things are done in unison.
That psychedelics can worsen mental disorder?
Psychedelics can help you process bad experiences, and it can generate new ones. You can unlearn unhealthy biases or gain new ones. The papers tend to discuss this.
This claim, that doing it alone is unlikely to work, or likely to worsen your situation.
> That psychedelics can worsen mental disorder?
That sentence is not the same as the previous claim.
And I didn't suggest worsening was likely, but I think it's about just as likely as stumbling into a real treatment effect by accident, which is what I said. I'm not sure what data exists on the relative probabilities here, probably fairly little.
Most of the time, you'll just achieve nothing at all other than maybe an afterglow that makes you think you're better for a couple of weeks.
I've used a lot of different psychedelics in different settings over the years(pribably somewhere around 100 experiences with something like 10 different psychedelic drugs), Exactly once I've had a concrete, non-temporary improvement in mental health. Another time I had such a bad experience I took me months to properly recover.
Most of the times I felt like progress was being made, but it turned out just to be an afterglow effect that quickly went away.
Sometimes we don't have good data for good reasons.