And desperate people will cling to nearly any promise form snake oil salesmen.

There are a couple of areas I know something about. Alopecia areata (hair loss) and Asperger's Syndrome (a form of autism) from personal experience. Sometimes it is all I can do to be civil to people who pop up with the definitive miracle cure for one of these.

I also get very tired of those who claim that Big Pharma or Big Medicine systematically withholds cures for various diseases so they can make more money.

Dentists. They used to make a lot of money from filling cavities. Then kids started getting far fewer cavities, mainly because of (gasp!) fluoridation. But have dentists shut down in huge numbers? No, because there are still plenty of dental issues to deal with. Similarly, if (for example) one kind of cancer becomes completely curable with a cheap and readily available medicine, do you REALLY think it will be withheld? I don't. Because even if all cancer becomes readily curable, there will still be plenty of health issues to keep all of the doctors in business. And Big Pharma.