Technology aside for a moment, is there really a difference - conceptually - between tweaked/manipulated/repurposed samples and re-re-re-re-reused (yet repurposed) blues and 50s rock tropes? Also, in the '60s, there were often multiple artists covering the same song in a short span of time (a few notable cases of two artists' versions of the same song on the charts at the same time). Many of the Beatles' early hits were covers, even. Technology not set aside... it's kind of an anachronistic argument. But the prevalence of TV, the rise of recorded music (as opposed to strictly, or predominantly, live), the recent shift to the LP format, etc... are all things that certainly helped The Beatles, and can be chalked up to technological (or cultural) changes well beyond them specifically.