Great post Simon.
Iain, I think that some of the Beatles themselves would tell a different story! As a band John, Paul, George and Ringo had a wonderfully productive 10 years or so. But from what I gather from recorded interviews, by the end John Lennon and George Harrison felt that being part of the group was no longer in their own interest. Seemingly things were being held together at that stage by an overly dominant McCartney, while the others felt that the existence of the band was serving Paul’s interests disproportionately.
Have a listen to the Lennon Wenner/Rolling Stone 1971 interview, where John Lennon says:
“That is one of the main reasons the Beatles ended. I can’t speak for George, but I pretty damn well know we got fed up being side-men for Paul.”
I reckon if you could ask them (it’s shame we can’t), Lennon and Harrison might have considered their post-Beatles music to be their best, and most authentic work.