Be careful with correlation and causation here. A lot of the people I knew in the psychedelic trance scene were already heavily into various forms of spirituality before they started using drugs.
That may be true, but it doesn't lessen the risks. People who are predisposed to mental illness don't necessarily know that they're predisposed to mental illness.
If we're going to have honest discussions about the risks, it's important that we avoid blaming the victims by post-facto assuming that people harmed by a drug somehow had it coming due to an invisible predisposition. It doesn't change the math at all.
If after taking psychedelics safely and guided by a community that does them responsibly they discover that they are predisposed to mental illness earlier than just waiting and getting symptoms because their brains deteriorate with age, then that's a good and not a bad thing.
A predisposition doesn't mean someone is destined to become ill, and it also doesn't dictate the severity of the illness should one arise.
The problem is that psychedelics can induce mental illness in those who might have never become ill, and psychedelics can induce severe psychotic disorders in people who would have otherwise lived normal lives.
These kind of delusions seem to be ego-syntonic, so discovering them about yourself won't lead you to get them treated. You have to force it on people if it shows up.
They can start therapy or get psychiatric help sooner, or make lifestyle changes sooner that will result in them living a fuller life of being present for more of it.
Contrary to what you read or hear around some places, we don't know if psychedelics "accelerate" the onset of symptoms of degenerative mental conditions. For example you may experience schizophrenia-like symptoms under the influence of LSD and while that may be a warning that you need to see if you will actually develop "natural" schizophrenia, maybe you will never do. But maybe you will! and you would have never known without that "bad trip". It's true that there's a lot of anecdotal evidence of subjects that don't "come back" after a psychedelic induced breakdown, particularly when they are in the bipolar spectrum. But most people, even the ones that actually have mental conditions, do come back and a lot of them report it helps with symptoms or commodities: most notable depression or social anxiety but sometimes also paranoia, suicidal idealization or intent to harm others.
If you are interested in the connection between psychedelic use and mental illness you should look into the work of researchers that adhere to the psychotomimetic theory of the drug/brain interaction. A good recent place to start is this compilation: https://www.sciencedirect.com/book/9780128047910/the-complex...
While it's on cannabis use, for which we have way more evidence of it causing early onset of degenerative mental conditions than psychedelics (even LSD), it does reference a lot of studies about the effects of psychedelic experiences in individuals prone to neurodivergency.
> we don't know if psychedelics "accelerate" the onset of symptoms of degenerative mental conditions. For example you may experience schizophrenia-like symptoms under the influence of LSD and while that may be a warning that you need to see if you will actually develop "natural" schizophrenia, maybe you will never do. But maybe you will!
This sounds like there is only downside risk.
Schizophrenia can be hard to treat. Bringing it on ‘early’ seems like just losing good years, even more so if there is a chance it would never have developed at all.