Psychedelics don't trigger psychotic breaks.
Of course they do. Any hallucinogen has the capacity to. I'm not saying it's particularly prevalent, or occurs for everybody, but it's certainly a risk factor. And even if it's very small, the mere possibility is scary enough for a lot of people to turn them right off it.
I'm not hugely knowledgeable on the subject so I don't really want to get into an in-depth discussion on the merits of various drugs. But it would be naive to claim that any psychoactive drug is without risks, or that all drugs have the same risks, or that all people's attitudes to those risks are or should be the same.