John Lennon was a very good rhythm guitarist (Don Everly was a FANTASTIC one!). Is Quincy Jones even aware of the function rhythm guitar plays in Rock ’n’ Roll music? I doubt it. That is just one example of what makes his opinion of The Beatles as musicians irrelevant. The fact that playing rhythm guitar does not take a lot of technique does not mean it is easy to do well, or that it does not require skills of a particular sort. Technique is a matter of the body being trained to perform physical acts, and is only one element of musicianship. Part of superior musicianship is knowing what NOT to play (a non-technique skill), and that is a major element in the playing of rhythm guitar. Rock ’n’ Roll music greatly benefits from superior rhythm guitar parts. That’s why Jeff Lynne’s production of Tom Petty was so successful; there are acoustic rhythm guitar parts all over that album, and Petty’s music is the better for it.
The thing is, Jazz guys don’t respect Rock ’n Roll as a music, and don’t understand the principles involved that make one practitioner of it superior to another. The skill set involved in R & R music are very different from that in Jazz. As Keith Moon replied when asked if he could play in The Buddy Rich Big Band: "No, and Buddy Rich couldn’t play in The Who."
