Pill mills were shuttered, but you'd be surprised at how creative people are when they need to feed their habit. There are doctors and pharmacists all over the place that are either:
1.) Being explicitly blackmailed by prescription drug addicts.
2.) Whose employment is completely dependent on prescription drugs because their patients demand prescription drugs as a quick fix for their problems. There are people who literally feed clients to those doctors because they know they are afraid to tell their patients no when they ask for prescription drugs
3.) Don't bother to find alternatives for their patients that don't involve prescription drug abuse because it is a faster method of getting their patients out of the office.
For 1 & 2 specifically;
Doctors receive an itemized DEA report each month for each patient who's prescribed controlled substances. The reports contain all controlled meds prescribed to that patient, from every Dr.
I saw my first DEA report 20-odd years ago, so they're nothing new. Each report is a tap on the shoulder to remind Dr.s that every controlled prescription they write is being closely monitored. Patients are monitored exactly as closely as Dr.s, they just aren't informed every month.
So - the volume of prescriptions inferred by #1 & #2, would immediately attract DEA attention. Both Dr and patient would be in cuffs before drug-seeking patterns had time to develop.
What is entirely more likely than 1&2, is that the endless demonization of prescribing opioids - and the continual LEO threats against Dr's who prescribe meds in a way that the DEA doesn't like - is increasingly frightening Dr.s away from treating pain in an effective way.
Your #3 contains a number of assertions that would be difficult-to-impossible to prove (or disprove), when strung together like that.
I agree with all of your points, including the fact that I do not have supporting data.
Just keep in mind that the people who are really good at skirting prescription drug laws do everything to make their operations look innocuous. They use regular family practices and they dont fill any more controlled substances than any other family practice by percentage of perscriptions. You're never going to see these people showing up in any reports, there won't be any supporting data.