It's a pessimism thing.

I've had doctors (in America) tell me to not worry about medical issues and others recommend a battery of tests to look for correlated but uncommon issues. My current GP recommends basic, palatable approaches to diet and exercise that have nothing to do with giving them money (and, presumably, reduce my medical costs with them down the road.)

I've also had doctors suggest that I get an issue reclassified so they could do surgery. That could be viewed as them wanting money, but I view it as them seeing a problem that can be fixed by surgery because, as a surgeon, that's how they approach problems.

I don't think that fasting is problematic to the medical industry in the US. And if it is, it's not because it's zero cost. Doctors love zero cost interventions. The real challenge is just the standard medical challenge: 1) educating doctors as new evidence comes in, 2) doctors educating patients, and 3) patients complying with the intervention.

Are you asking if your anecdotal evidence is sufficient to make an inference for all of Europe and the US?