I had forgotten The Rutles. Lennon's character was called "Ron Nasty" in that movie. In that Bramwell memoir I mentioned, Lennon came off as very weird and anti-social from a very young age. Even before Yoko, he seemed kinda "off". Maybe she saw him as a kindred nutjob.
Before Yoko, John was definitely the leader of the Beatles, he was the one who pushed them, definitely the strongest personality of the band.
After Yoko, it seemed he didn’t care at all about the band, and that’s when Paul took over.