While the Beatles' audience might be preponderantly pubescent, at the same time their musical ideas attracted and influenced serious, sophisticated, professional musicians. A substantial part of their popularity among the young was perhaps more sociological than musical, and it seems safe to assume that a large number of teen-age Beatle enthusiasts had little or no concept of the musical content of their recordings. Their exuberant vitality, their delicate handling of sentimentality, and their real lyrical gifts offered something new and fresh to popular music. At the same time, their topical, carefully-coded lyrics, with concealed references to sex, drugs, and rebellion, captivated restless and uncertain youth everywhere. (Although their rebelliousness has proved to be partly ironic, and not half so destructive as their critics have assumed.) Their extravagantly eccentric dress, wild hair styles, and public antics implied a lifestyle which proved instantly attractive to the adolescent….
The Beatles' importance to popular music, however, had little to do with screaming adolescents, for they brought to it a fund of ideas and a musical style that have since exerted enormous influence on the field. Whatever their eccentricities of dress and behavior, they were, as a musical organization, highly skilled, imaginative, daring, and thoroughly competent professionals. (p. 352)
Russel Nye, in his The Unembarrassed Muse: The Popular Arts in America (copyright © 1970 by Russel Nye; reprinted by permission of The Dial Press), Dial, 1970.