"Don’t eat anything your great-great-grandmother wouldn’t recognize as food. (Sorry, but at this point Moms are as confused as the rest of us, which is why we have to go back a couple of generations, to a time before the advent of modern food products.) There are a great many foodlike items in the supermarket your ancestors wouldn’t recognize as food (Go-Gurt? Breakfast-cereal bars? Nondairy creamer?); stay away from these."
All those foods that you mentioned, a 19th century mom would recognize as food. Just not her kind of food.
I think that one of the weaknesses of Pollan's saying is how it can be interpreted by people who haven't read his other stuff. Taken literally, someone much younger than Pollan might think that Pollan advocates for broccoli to be boiled and smothered in Velveeta.
(Food diversity sucket in our grandparent's era. )