That can't be emphasized enough in this debate. In short: if you arrived at some magical scan or test that indicated the presence, by degree of nerve stimulation of hand-over-a-hot-flame-type pain, and only prescribed painkillers to people over some threshold, you'd still be both excluding people who were personally suffering as much or more as those who made the cut, and including people who did not experience the same discomfort.
The human sensorium has a lot of experiences in common, but also a ton of differences.
This is a well-understood phenomenom about screening: screening people usually (not always) causes more harm than it fixes.
Back when "pain is the 5th vital sign" was being pushed people thought opioids were not addictive if used to treat pain. https://www.bbc.co.uk/news/world-us-canada-40136881
And there are drug reps telling you this medication is not addictive and that you're being negligent in leaving pain "untreated".
So, you ask everyone if they're in pain. A load of them say "yes", and you can't afford to give them physical therapy and psychological support but you can give them opioids which are dirt cheap and you've been told they're not addictive if used to treat pain. You end up flooding communities with opioid meds. You have a bunch of people still in pain, and with an opioid addiction. And then you have their friends and relatives who aren't in pain but who want to try these meds recreationally getting hooked.
It's a public health disaster.
To answer your question: ask people about pain, but set expectations first. Opioids are a poor choice for most people with long term pain.
Not much better than palcebo for neuropathic pain, but with more side effects and with risk of addiction: https://www.cochrane.org/CD006146/SYMPT_opioids-neuropathic-...
No better than paracetamol for long term back and joint pain: https://discover.dc.nihr.ac.uk/content/signal-000610/opioid-...
But what I think will happen, and some of the comments in this thread illustrate, is that the pendulum will swing in the other direction. Medicine doesn't know what to do with chronic pain. We can't define it, we have imprecise anatomic correlates, and no patient wants to be told that some fraction of it is in their head even though it's likely a combination of neurologic and psychologic factors. I remember throwing some obvious seekers out of my office but I had a lot of credible chronic pain patients when I left general practice, good people laid low in difficult ways, and I wonder what's happened to them since.