It's conceptually that simple. But like many simple concepts implementation requires understanding and dealing with the rather more complex environment and circumstances around the problem in the first place.
I would suggest that none of the current solutions actually take into account the complex environment and circumstances around the problem. We don't exactly create cultures of resiliency right now and most of the approaches on both the right and left sides don't tackle the problem of resiliency either. Advice to someone that they should "just not do that" aren't working either. There are no shortage of people who told and are telling addicts exactly that. What do you suppose would make them actually capable of following that advice?
Contrary to that we need drugs in many situations in life. There are the obvious examples where you need opiates for alleviation of extreme pain and the less obvious ones like using stimulants to help manage ADHD but there are many other medical and non medical reasons. Caffeine and alcohol are both useful in daily life but I believe many other drugs could be similarly useful if properly adopted into social norms. Yes there will always be cases of abuse but our effort should be on helping those individuals to recover rather than enforcing a blanket ban that does much more harm. In fact, I believe that many of the people who become addicts would not if they lived in a society where there were social structures that allowed them to use the appropriate drugs in the right amounts to help them function in their daily lives.
If your solution is to convince every single person in the world who hasn't used drugs to just not try them, then you still have to deal with the ones who have!
You do realize that many addicts (of opioids) got that way after using legitamely prescribed pain-killers? And many others have other underlying health problems (often mental)?
