For 1): Yes, the photoelectric effect is frequently told. But that's not what the article is referring to here, it is foreshadowing its discussion on the semiclassical treatment of the photoelectric effect (by Lamb and Scully). This is the "messy, largely forgotten" part which is rarely discussed. I saw it in a graduate quantum optics course, but even at that level I'm not sure it's part of the standard curriculum.
OK that makes sense.