I think it’s pretty common for people to think doctors are great at treating acute conditions (stroke, broken bones, severe illness) but distrust advice on chronic conditions. So this may not be something they see as a discrepancy. And I can kind of see it if I squint - people on lots of medicines are often sick, and people on none healthier, and they may think this causation runs in the opposite direction, that they can magically join the healthy group by not taking medicines.