Nice article. I used the "$9,999 on where to put it" for years; didn't know it was Steinmetz. After reading biographies on Tesla and Heaviside, I suppose Steinmetz is next on my list.
I don't see any claim in that article that this is a myth. They merely discuss variants of the story. Fwiw, I have heard Steinmetz as the origin of this, a possibility they discuss in the article without explicitly confirming or refuting it.