OxyContin was prescribed by doctors that believed it was not addictive to patients that were not yet addicts. The prescription is temporary and ends, so then there is a new illegal drug addict.

Speculating here, the difference is two-fold:

(1) The drugs shouldn't have been prescribed in the first place. This system was creating the cycle of dependence, not attempting to manage it.

(2) Oxy and other opiates were prescribed for specific medical issues rather than recreationally. That leads to drug-seeking behavior once the normal course of treatment wears off, and eventually when cut off from legitimate supply, illicit alternatives.

Don't forget manufacturers of "long release" versions requiring prescription of fewer higher dosage pills instead of more smaller and incidentally cheaper ones.

Yes, it increased consumption by creating new addicts. Because, as with cigarettes, addicts are good customers. But it was inability to keep getting prescriptions that caused overdoses and death. Because you had all these ~middle class addicts switching to heroin, without a clue how to use illicit heroin at least somewhat safely. That, and the increasing use of fentanyl to increase potency of highly cut heroin.

It is different because you have to prove you are an addict to get the free heroin.

The oxycontin crazy created opiate addicts in droves because it was given out virtually unchecked to non addicts.