Lennon could be melodic and musical yet his attitude or vibe could takeover and make the music sort of secondary thing. That will always strike a lot of people as more interesting than "pure" music. Ex: some people would rather hear chords played on a slightly abrasive guitar then on a Melotron keyboard.

Like someone could paint a nice picture with fine detail and another artist could paint a rough picture that has some intensity. Some people will gravitate to one or the other.

Also to be remember is that McCartney was left-handed so that is supposed to make a person more in tune with his or her right/artistic brain. So Paul was truly gifted to do what he did. John Lennon being right handed means it seems John had to do some deep digging to come up with his expressions.

Like some people like highly orchestrated classical music because that seems like true musical inspiration had to be behind creating a symphony and some like raw punk rock because that seems like someone breaking through limitations and music with their attitude.

Paul could do some forceful things here and there and Paul deserves credit for that but those who like a little drive and passion know John had to be digging deep. And on top of that, when John created a very musical song like "How?" on the "Imagine" LP/CD, you begin to wonder how John was able to do it. So that's more angles for John.