"Sorry to say this (and I like the Beatles as much as anyone) but Lennon did a disservice by not learning to read music. He gave birth to generations of lazy kids who think all they have to do is play and everything will come to them. When it doesn't, they abandon it."

Sorry ~ isn't our main focus hereabouts supposedly FOLK music? While folk music in our post-modern/post-recording-technology age is certainly played (replicated, actually) by many varieties of musicians, including the classically-trained and the ultra-literate, the "source musicians" we're ostensibly emulating were much more likely to be utterly unfamiliar with standard notation.

Sure, the best players among them had a thorough (but often more intuitive than didactic) understanding of harmonic theory. But I'd wager that very few could sight-read from "dots," and fewer still (by far!) knew, or could possibly care, about the existence of B-sharp.

Not just John Lennon ~ hundreds, even thousands, of the anonymous players and singers who have left us centuries worth of folk tradition have had little or no facility with written musical notation. So what?