I was amused but not upset about Paul's generalizations -- I agree that he/the show is over-generalizing, but I don't take it personally, maybe because I don't really feel a strong identification as "American" (I am American, but to me it just happens to be where I'm from - not my identity). I love the cultural culinary differences and didn't feel a need to bash British recipes in return for them saying American pies are too sweet/disgusting.
I also couldn't care less about Paul's personal life. I just watch him on the show and don't pay any attention to that. He can be arrogant, but he doesn't particularly bother me. *shrug*
Anyway, maybe when they said "American pies" they meant pies that originated in America and are not generally made elsewhere? For example, of course we make fruit pies in America but they are not uniquely American, as Britain also makes them, so that's why they are not under the definition of "American pies" as defined by this episode. I don't know, just speculating.
I love the little historical segments. It didn't seem weird to me that it was stuck in the middle - isn't that how they air it in the UK? It's not supposed to be about the specific thing they're making in that episode, necessarily - just an interesting historical tidbit that relates to the general topic of that episode (pies, in this case). Eel pie sounds disgusting but it's fascinating to learn about the historical aspect of it and how they just used what they had access to. I was watching a British show set in World War II and they kept talking about going out to get eels for dinner. I wondered at the time if that was common and now I know that it was!