I bet the Stones would agree with his assessment.
This is an old argument that dates back to the the early Seventies. It has never been resolved because there are hardcore fans of both bands out there. Truth is they respect each other and I see nothing wrong with McCarthy’s comments.
Yes, McCarthy was into more of the pop genre then Rock, but his music was also enjoyable. McCarthy and Wings were part of a genre that include a lot of top “Rock” bands of the time. Compared to the Seventies early Metal bands, Black Sabbath, Deep Purple, Led Zeppelin, Pink Floyd etc... Wings was a absolutely a pop band. It is a matter of taste and I enjoy Wings a lot more now then I did at the time. McCarthy was always the balladeer, Lennon, Harrison were the edgy types that liked to experiment. That was what made the Beatles work. Do not forget Ringo, he has had a lot of hits with a little help from his friends.
McCarthy did not lie, it is true that Lennon broke the band. He came in one day and announced he was leaving, there was an apparent unwritten agreement they would not announce the breakup until release of the last Beatles album. McCarthy decided for his own reasons to jump the gun and announce he was releasing his first post Beatles album. That caused some acrimony. But, while everyone dances on pins and needles if you look at how he treated his family especially after Ono, Lennon was a bit if a self centered bastard. Loved “Double Fantasy,” though, except the crap obviously written by Ono. When compared to the Metal music of that time, Double Fantasy was a pop album.