What they did musically and in the studio was inventive and ground-breaking. I doubt you can say the same for the Backstreet Boys. I can somewhat understand criticizing very early Beatles music as being more boy band fluff, but by Rubber Soul at the very latest (I might peg it at A Hard Day’s Night, even), they were in a league of their own, songwriting-wise, and I cannot think of another band as musically inventive and interesting, that did so much to expand the definition of what is “pop.” Harmonically, melodically, song structure wise, they were constantly trying out new ideas.
I mean, if you want to nerd out musically, how many pop bands do you know of that can throw in an 11/8-4/4-7/8 passage in a song (as in “Here Comes the Sun”) and make it sound so natural and completely pop? Or the classical-modal-pop fusion of something like “Eleanor Rigby”? If you like this sort of detailed musical analysis, read Alan W. Pollack’s Notes On… series.
And I’m not going to even get into all their studio innovations.
I actually don’t even own a single Beatles album, but Beatles love is not “embarrassing.” In the end, it’s the music the counts, and Beatles music is so natural and flowing that one often doesn’t realize the amount of sophistication going on in. They had an impeccible ear for melody, harmony, and orchestration, and very rarely delved into rock cliches. I honestly cannot think of a single band that has contributed as much to the development of pop music as the Beatles.