From what I got from the article, the TL;DR version of this, is the "rat park" experiment: http://www.stuartmcmillen.com/comics_en/rat-park/
I've, since reading the study, thought about this a bit, and while I'm not an expert in the field, here's what I'd say:
Firstly: as this article and rat park show, if you're in a terrible, or even uninteresting environment, it kinda makes sense that you'd be more likely to look for ways to escape that. Drugs are a great temporary solution to a bad environment (Of course, they have consequences, and don't usually FIX any problems, but, they get you through that day).
Secondly: I would guess that the scary propaganda we're constantly fed about drugs DOES drive SOME people away, but it drives the wrong people away. People who like their lives are probably scared to death of, say, Heroin, or Meth, because those drugs have a dangerous reputation (it's grossly inflated, BECAUSE of this mechanism, I'd argue, but they are dangerous). On the other hand, if you don't have much to lose, why not try this option? It seems more reasonable because the "risk" doesn't seem as big. I just need to get through my terrible day. Why not drugs?
Lastly, the appearance of addicts and users to the general public is HUGELY negative. Why? Because considerate users/ functional addicts are MUCH harder to spot than dysfunctional addicts or people who don't respect their drug of choice.
If you're an asshole, and take a bunch of psychedelics, you MIGHT do something kinda nuts, because you're an asshole, and suddenly, you're walking around naked. And people hear you were on, say, LSD, and go "fuck man, that's weird."
If you're a desperate heroin addict, you might wind up on the street, without much shelter or food, and you look TERRIBLE as a result. Or if you tweak for a week, etc. You look haggard, and you're not trying to hide the track marks, and people connect the dots and go "FUCK man, why would you ever try Heroin/Meth/etc."
Whereas, if you're a more responsible user, you're not showing up to work fucked out of your head. If you're a functional addict, at least you don't show up to work wasted (you might be altered).
Anyway, I think I might be just hopping on my soapbox, so I'll cool it for now. I just think approaching the problem, as the author said, from the perspective of "why do users turn into addicts?" and addressing THAT problem, is how we should attack this.