I did a lot of club drugs in my 20s and knew a lot of addicts and alcoholics (although personally once I decided to quit everything around 30, I just stopped cold turkey with no problems), and although I personally avoided opiates I knew people who didn’t and had very hard lives as a consequence.
You are correct that most of them had hard lives to begin with. Happy people with strong support networks don’t tend to use heroin, I wouldn’t think.
The psychological problems that lead to addiction of any kind are very deep. The addiction itself is just a symptom.
What this decision is - is just a declaration of "let's stop fighting symptoms, maybe that will allow us to see the root problem".