Well, I don't think it's a case of them mixing it up so much as a different use of the phrase "Classic Trilogy". They're using it as a moniker to delineate between the Original Trilogy and the Prequel Trilogy. They're calling the OT the Classic Trilogy. So, in that sense, Classic Trilogy refers to the OT, the SE, and the eventual UE. So, to paraphrase Obi Wan Kenobi, "what they said was correct, from a certain point of view."