It does go pretty far in service of Drugs Are Bad. There's a Sinister SurveillanceState in the pursuit of a War on Drugs that results in no one trusting anyone else enough to form genuine attachments; the weak and powerless are preyed upon by drug companies in order to profit from them is equally reprehensible. The horror of all of this is delivered with the subtlety of a sledgehammer, but this is understandable given that Dick was talking about issues relevant in his time and perhaps even in the modern day.
It also goes pretty far to point out the hypocrisy of rehab clinics and the system itself, also playing heavily on the idea that people who have been broken or tormented by drugs or mental illness are not only discarded but invalidated by their view on reality... in essence, no one would ever believe that the rehab clinic is in fact using drug burnouts to farm the drug itself. Philip Dick likes his irony.
Harsher in Hindsight: The story takes place after the U.S. lost the War On Drugs. As of June 2011, the Global Commission of Drug Policy has declared the war a failure. Uh-oh. And given that the US has been in an opioid epidemic - wherein deaths from overdose of opiates beat out vehicular and firearm deaths starting in 2015 - this is now even harsher, especially in light of the pharmaceutical industry's successful push for deregulation in the late '90s that led to it.
Values Resonance: The book's Aesop and theme became more relevant with the general controversy of War on Drugs (namely mass incarceration and racial profiling with no effect on stemming drug-crimes) along with surveillance and loss of privacy in recent era.
Genius Bonus: The film is set in Orange County, California, and notable Orange County landmarks visible from Interstate 5 get passed by during scenes of driving.
Magnificent Bastard: Audrey and Mike are two cops who have tried to infiltrate New Path, a rehab company which is secretly flooding the drug market with Substance D. To this end, they get Bob Arctor hooked on Substance D by having Audrey pose as Hank, his boss, and Donna, his supplier. With Donna supplying him the drugs and Hank ordering him to spy on himself, they drive him further into addiction so that he'll be forced to go to a New Path rehab. While there, Mike, as an orderly, has him transferred to a farm. They later debate the moral and practical aspects of the plan, with Mike thinking it'll be worth it for future generations and hoping that Arctor has enough function to take back some evidence of the production. His hope proves well-founded when Arctor takes a flower that is one of Substance D's ingredients, planning to give it to his friends when he sees them on Thanksgiving.
Retroactive Recognition: One of the film's trailers featured "Teen Angst" by M83, long before they became famous for the radio hit "Midnight City" or making songs featured in big-budget movies like Oblivion (2013) and Cloud Atlas.
. Uh-oh. And given that the US has been in an opioid epidemic