The term snake oil is actually especially fitting for this, due to its origins.

In Britain in the 1700s there was a somewhat common recommendation for using rattlesnake oil from the fat of the snake for skin diseases/rheumatism. The efficacy is debated but it’s got some amount of potential for change (if not help).

This turned into people in the US selling mineral oil as “snake oil” as a total panacea. So a product that actually could do stuff being used as the poster child for a completely useless product that can solve every issue ever, buy as much as you can today.

Snake oil indeed.