This. I am all for legalization but it’s not a safe drug. Induced schizophrenia by weed can be a thing if you carry a specific gene.
EDIT: That is, I don't think we have sufficient understanding to say whether pot abuse causes schizophrenia, or schizophrenics are more likely to abuse pot. Given what I know of how awful a ride that is, self-medicating that devolves into abuse seems far more plausible to me. Further, there's research that takes into account family history of these mental illnesses out to 3rd — and further — degrees, and which suggests a much stronger link between that and the illness, than the drug use.
There is of course a risk with any mind-altering substance that it might trigger a latent or occult mental illness. Those odds go up, sometimes significantly, with more powerful substances, and even more so when the user has any genetic predisposition towards those conditions. There's also a risk of having a difficult or traumatic experience, which can likewise increase with dose or different substances. That said, those of us who work with these substances intentionally often find that those experiences can be where the really transformative stuff happens.
EDIT: Phrasing
The strength of a drug like LSD takes my breath away compared to something like pot.
If anything, a more dissociative substance such as salvia would be more along what I'd call a "hard" one. Or perhaps 5-MeO-DMT.
This is correct. But we do have sufficient statistical evidence to rule out _large_ negative effects. We do know that cannabis is very unlikely to be as harmful to physcal and mental health as alcohol.