Hi,
I LOVE old R&R from the late 50s, 60s, and early 70s.
I'm Beatled out completely, because they've been so over-exposed (not so much over-rated I reckon, different thing). They do have songs which are quite difficult to perform yourself on stage, but I'm not sure what that signifies. Talent perhaps
Maybe it is the difference between the studio and the stage, like it was with the Beach Boys.
You have to examine it critically. They mastered 3-part harmony I think, fairly early, from their grounding in Hamburg - "This Boy". They understood the principles of writing pop songs very well, eg having a good hook - "Anna", or "Norwegian Wood". And they weren't bad instrumentalists either. We don't need to talk much of McCartney there, but study Lennon's rhythm guitar in "Cry for a Shadow", or Harrison's lovely little solo in "All my Loving". If you are a Harrison fan, look at "Roll over Beethoven", in which he is the front man, voice and guitar.
There were a lot of other good bands then, really good, most especially the Hollies (oh dear, Tony Hicks), but the Beatles definitely got there first
Cheers