Retribution provides almost no societal benefit. Most of society doesn’t know or care about any individual crime. Rehabilitation of a single member however will benefit all of society, as you can’t predict all possible social interactions of a single person.
Social order, the people wronged want to know that the culprit suffered for it, otherwise said people will start to feel the judicial system is disconnected from justice itself.
I mean, why do you think Lex Talionis is that historically universal?
The caste system and human sacrifice also provide social order. Medieval system of peasants and lords and kings provided social order. Spanish inquisition and torture provide social order.
For my part, I consider inflicting suffering to be fundamentally immoral, because the "moral" justification for retribution relies on the notion of free will, and there is no rational case for free will.
1 in 100 people (or os) is schizophrenic. It's quite predictable what happens when a schizophrenic person takes psychedelics. I am not saying this is your case here. However, if anything your single case example shows inadequacy in the health- and social care systems and not unpredictability of DMT.
If a person hadn't experienced a debilitating depression it's hard to imagine what another person is experiencing. All those walks in the park and hobbies sound logical and wonderful, on paper. Reality is a bit different.
I agree that it is quite difficult to bootstrap a hobby practice, or repeatedly involve oneself socially when depressed. Speaking from personal experience in the deep dark pits, what I mean is that we should look at the problem through the lense of the BioPsychoSocial model.
Modern medicine is irreplacable but relying solely on medication is a pitfall of modern treatment. It turns out, for example, that chronic pain and depression are interlinked. A messed up neurochemical balance contributes to the erroneous interpretation of signals by the brain as pain (even when no bodily damage exists anymore). So what I'm saying is that while it may seem pointless initially to do that which falls flat in the estimation of a depressed mind (say due to anhedonia) those brief but regular walks in the park contribute to re-stabilization of neurotransmitters along with the medication.
