These retired agents didn't see the drug war as a war on "bad guys," but as an effort to stop the destruction drugs wrought in people's lives. After all their work, their own government undermined their efforts.
My own doctor was taken in by Big Pharma's sales pitch and wound up going to prison for over-prescribing their pills. https://en.wikipedia.org/wiki/William_Hurwitz. Though to hear Big Pharma tell it, there was no such thing as over-prescribing.
If you want to get an idea of how out-of-hand the prescription frenzy got, take a look at John Temple's book American Pain, which describes the pill mills in South Florida. Towns in Appalachia used to send charter buses to these pharmacies. After a 12-20 hour bus ride, each passenger would pick up hundreds or thousands of pills, then ride home to sell them in their small country towns.
Some of the pill mills, which were fully licensed by the state of Florida, were cash-only and would haul garbage bags full of money to the bank each day at closing. For a summary of Temple's book, see https://adiamond.me/2020/01/american-pain-by-john-temple/