Synthesiser vs robot musicians

Toyota have created a robot that plays violin. This robot is roughly human shaped and plays the instrument in the same fashion humans play it. If I were to design a robot to play instruments I would not design it human-shaped and playing the instrument the way a human plays it.

The robot can have more fingers than we have, one for each string/fret combination on the guitar, one for each hole on the flute. The robot guitarist would also have one plectrum for every string. This would allow the robot to play the instrument faster than humans can. Doing what a synthesiser does, but with real sound.