I still see the Iodine doctors and supplementers as just being ridiculed and written off as quacks. It does not become self evident until its acceptance has passed the tipping point when even the ill informed know that it works.
"When a true genius appears, you can know him by this sign: that all the dunces are in a confederacy against him."
Jonathan Swift
Good ideas and good products can also develop their own crowd of opposing fools; to the point where you really have to question yourself extra diligently if everybody is in agreement on something.