If the Beatles represent one end of the spectrum of business models for music (all efforts support the sale of the recording), on the other end is the Grateful Dead, whose business strategy invited free copying in order to sell tickets to concerts and branded paraphernalia. Former Dead lyricist John Perry Barlow has posited that the Dead business model will ultimately prevail for all artists. This may or may not be true, but Barlow does not explain how this would have worked for the Beatles, who were simply too popular to venture before a live audience. The Beatles were recording artists, the Dead brand marketers.
It would be wrong to assert that creative individuals such as the Beatles would never have developed into artists in the absence of a copyright regime. But it would also be wrong to say that the absence of a copyright regime would not have made a difference. What that difference might have been, we will not know, until another group as talented as the Beatles appears, operating in an “information wants to be free” environment.