Oh, now, I wouldn't go that far. :) Those were two stellar albums...but you can't discount their subsequent works entirely. "Magical Mystery Tour" was a throw-away, but Sgt. Pepper was a masterpiece. "The White Album" was a wonderful mix of hit-or-miss classics. "Let It Be" was cathartic.
Overall, I'd have to say that there never has been, nor will there likely be, a single group that has such impact on the music world, or the world in general, in such a short period of time as the Beatles had.
I wasn't suggesting that they did nothing worthwhile thereafter.Sgt Peppers was excellent,the White Album had several great songs...same with Abbey Road.