Yes, the article does not say that everyone who takes Accutane is gonna go Kurt Cobaine on us any more than everyone who takes Prozac is gonna go postal. It is just a a warning of what could happen due to the problems with lowered levels of seratonin.
Kind of like the one you see that says "slippery when wet". Hundreds of people may barge right ahead with no apparent problem, but sooner of later, some of us are gonna bust our tails.