"To say that someone is harmed by finding out what doesn't work is a bit of a stretch."

Conversion therapy

Bloodletting

Rydalin

12 step / AA

Every quak remedy that ever existed

Good grief there's an infinity of things that are more harmful than doing nothing at all, and cost a lot in real harm just "to find out what doesn't work", and yes of course even mere conversation vs drilling holes in your skull can be harmful all the way up to death and even collateral death other people when someone they love is essentially killed or abused.