This is a fantastic take. I’d never thought about this before but you’re right that this might be Patient 0 of the modern rich white person’s exposure to cast iron and associated care.
“Mapp had inherited her grandmother’s skillet and used it often. It had a glassy black surface that no soap ever touched. Starling put it in front of her on the table.”
I read the series long after publication date and remembered going, “wait, the no soap thing has been around THAT long?”