I never said he wasn't an asshole, but he was the best musician in the group. He wasn't much of a lyricist, but without him the Beatles would have simply been a snobby art rock band with no real melody, except for the occasional George Harrison gem.
And as much as I like George Harrison, he could have never written enough material to sustain longevity without Paul and John. Paul had the best musical sense of any of them. John was more of an experimental poet. For the most part, his solo work appealed to artsy snobs, not music lovers.