Impala wrote:
What I don't like about this is that guitar playing may soon become an unnecessary and replaceable, old fashioned skill from the days when people played analogue instruments!
I doubt that will ever become a problem!
I actually started wondering about this a while back because there are similar videos with drums being played on a keyboard, for example. So the question become: Why would you need to play anything other than a keyboard? Especially since many other instruments can only play one note at a time.
My answer is that one requires a more direct interaction with the sound-producing mechanism for true musical expression. This is why classical instruments tend to be so simple - simplicity allows the musician massive control over the sound being produced, leading to huge expressiveness. The nett result is that these instruments tend to be more difficult to play for amateurs (e.g. no frets!), but in the hands of a master, they are like a musical link to their soul.
I have heard people argue that the move back towards old-fashioned analogue synths is keyboardists' way of acknowledging this. All those knobs and buttons allow more direct control of the sound, thereby at least partially emulating the expressiveness of more traditional instruments.
A guitar is interesting because one has control over how and where the strings are struck and also over how the strings vibrate, so a huge range of expression is possible. Think of techniques such as hammer ons, pull offs, palm muting, pinch harmonics, tapping and all the other playing techniques a guitar offers. And yet, the barrier to entry for an amateur is surprisingly low (e.g. frets!).
So if anything, a guitar represents a remarkable balance between ease of use and expressiveness which other instruments struggle to match. Hence its remarkable popularity.
*Climbs off soap box* ?