Got told a while back, "We don't play minor chords in Old Time music." I mentioned it to my fiddle teacher and she said, "For that matter, nobody played guitar in old time till the 20th century; before that it was just fiddles and banjos."
It reminds me of controversy in Javanese wayang about what's appropriate to the genre. I won't opine about what's appropriate, but I do believe that if people aren't arguing about what's appropriate to a tradition, that tradition is dead.