Earlier quoted context omitted.
Legalization is one key part; destigmatization is the other. Those who understand addiction, either first-hand or through research, understand that the root problem is not the drug/habit; the drug/habit tends to be the addict's best known way to sooth immense psychological pain. Shame drives addiction in deeper. So to actually help addicts, one needs to destigmatize the conversation, allow people to say "Hey, I'm in…
I’m not saying we punish the user, but rather find a way to minimize availability. Also, trauma is not always a cause for addiction. Lots of people suffer trauma and don’t get addicted, conversely we also have people with little trauma who get addicted.
It isn't a 1:1 causal link--virtually nothing is. But there's very strong evidence that unprocessed trauma is one of the core drivers of addiction.
It's constructive to think of drugs and addictive behaviors as emotional crutches. You don't help people with problems walking by making crutches illegal; you do so by focusing on treating the root cause, which may include taking the crutch away in a properly supportive therapeutic environment.
I'd also point you to the experiments dubbed "Rat Park" (https://www.psychiatrictimes.com/view/what-does-rat-park-tea...). Addiction is ultimately a social/emotional disease; the drug/habit is the symptom.