If it helps, here are a couple of things that you might consider:
- you likely know a lot of people who actively or in the past were experimenting with psychedelics, but you don't know that you know them because it is socially taboo and their experiences aren't super relavent to how you are interacting with them
- if you can accept that idea, then you might also consider that given a larger population of people who've tried it with few ill effects your anecdotal sample might not be an accurate representation of the psychedelic experience.
That second point would reconcile the "strange fervor for others to try it, even from people who have had bad trips."
There are indeed plenty of people mental health issues floating around, and while it's true that you may or may not know if these drugs will trigger a larger episode, that kind of life altering aspect of psychedelics not very common in my experience as a person who knows hundreds of people who have worked or played with these substances.
Those ideas are also based in my anecdotal experince, and perhaps it comes from a willingness to question some "fundamental axioms from scratch", but at the same time maybe that's a) not always a bad thing to do from time to time, and b) if your fundamental axioms are good there is no reason that you won't come back to them.