> what motive would the average person have to unreasonably hype up things like the healing power of shrooms?
It's something to hang a personality from.
There are a couple of drivers of ketamine's popularity for treating depression:
First, it actually seems to work astonishingly well for a lot of people (certainly way better than standard antidepressants), though not for everyone.
Second, it's a big money grab for ketamine "therapists" (I use "therapists" in quotes because many of them just sit around while you get your injection, and don't actually provide much if any therapy) who can charge $500 or more per treatment (which usually isn't covered by insurance), and people often come back for treatment multiple times a week or month for long periods of time. The cost of ketamine itself in these treatments is negligible.
An interesting development in ketamine therapy is the use of ketamine lozenges, which patients can take at home and therefore are way cheaper than having a medical team inject you with ketamine in their office.
Ego and I'm-better-and-more-enlightened-than-you attitude. You find this very often with cannabis smokers or "ents" as they fancy themselves. Also it's not that hard to find people peddling any type of dubious method : Homeopathy, crystals, acupuncture, Chakra meditation, putting up angel figurines. Often with the same amount of conviction and zealousness.
With natural medicine there's always people who point out the downsides, but with products made by the pharmacological industry, there's always those who defend SSRIs.
Is it even possible to gather some actual data on this issue without obvious bias either way?
The medical industry seems to have obvious motive to downplay any natural remedy as it doesn't make them money, and actively competes with their own products. On the other hand what motive would the average person have to unreasonably hype up things like the healing power of shrooms?