It was 50 years ago today....


...that the Beatles played their last concert on the rooftop of Apple Records.

https://www.rollingstone.com/music/music-news/beatles-famous-rooftop-concert-15-things-you-didnt-kno...
128x128mofimadness
Harold,

I doubt  a single one of the musicians you mentioned respectfully would agree that prog rock would have happened without the Beatles.  Anyway, the fact is that it didn't.  Revolver was released in summer of '66, featuring tracks with classical instruments, Indian instruments and the  track Tomorrow Never Knows, which pushed the envelope quite a bit. Strawberry Fields Forever was produced in late '66 and released in early '67, still ahead of the wave of forward-looking (or -sounding) Brit bands you mention (mind you, I also like those bands and "was there, so to speak"). 
One of the valuable (to me, at least) things I learned in school came from a music theory teacher.  I don't remember if we were discussing fugues or twelve-tone music or what, but he told me "it doesn't matter how complicated or sophisticated the method of composition is--what matters is 'is it good?'"  I don't think the Beatles were interested in creating genres or producing music for art snobs--just music that "is good."  Since we'll never know what would have happened without them speculation is pointless.
No doubt that Rubber Soul and Revolver were the albums that changed everything for The Fab 4. To my ears, specifically, the song "Day Tripper" was a key turning point. The band really found that Rock N Roll backbeat. Play it LOUD!

Happy Listening!
'Day Tripper' featured George Harrison's counterpoint guitar which was sophisticated and still is.
Two after Beatles records that deserve merit IMHO are 'All Things Must Pass' and 'RAM'.