'A "traditional" spaghetti sauce would be one based on tomatoes, . . .'

There's the rub. Italians didn't have tomatoes until after 1500 (they were brought back from the 'new world'), but they had pasta prior to that. Even today, many pasta sauces have no tomatoes in them. I don't mean to sidetrack this discussion, but the analogy poses a difficult question and I know I don't have the answer.