To Kill a Mockingbird comes to mind. The Hero’s Journey seems a pattern inherent in Story; myths were simply the first stories to be told, or, at least, to be recorded.
I was excited the first time I cam across supplemental material from a textbook publisher for a seventh grade novel that included a lesson on Joseph Campbell’s hero’s journey – not for a work on myth or fairy tale, but Jack London’s The Call of the Wild!
That was around 1999, I believe. Once Campbell was embraced by the textbook companies, seemed a solid sign his ideas had gone mainstream.