Vogel speaks of the book/author analogy, but doesn't carry it as far as he should. Using a BadAnalogy for the sake of the audience, requiring new art content in every game would be like telling Terry Pratchett he was wrong to keep re-using the Discworld as a setting, because we're owed "new everything" in every book. Or saying that Intel/AMD/ARM are cheating by not introducing new instruction sets with every generation of processor.
I've got no problem re-using engines, artwork, characters or anything else in games, as long as the narrative and situations are interesting.
-dB