Because do you know how difficult it currently is for chronic pain patients to be taken seriously? Do you know how debilitating and disabling it is to live with chronic pain or joint disease so severe that in your 40s, or in my DDS case, early teens, you cannot even walk upstairs?
Drs are reluctant to prescribe pain killers for fear of people becoming addicted, but at the same time won't let people under 60 have joint replacement surgery unless exceptional circumstances. Go to a pain clinic and be advised to pace, use mindfulness. Try pacing at work. That goes down well.
Then along comes "research" like this. Oh have a manicure and reduce your pain med requirements so we don't need to give you opiates anymore. Of course you can go to work with bone on bone disease and no pain meds because you've had a manicure.
It's offensive to people with these diseases. Do you have chronic pain from arthritis?