I don't think live coding makes live music more accessible to dabblers. Making live music that people enjoy listening to only takes a few dozen to a few hundred hours of instruction and practice, with either voice or instruments, and beyond the obvious a capella modalities, there's the harmonica, the borrowed friend's guitar, the recorder, the pan pipes, and so on, which together mean you can make pretty excellent music without spending much or any money. And it'll take you quite a lot of practice to outgrow a US$100 synth from Radio Shack. (Or wherever you buy them these days.)

By contrast, I have the impression that livecoding requires a great deal more knowledge to do in an entertaining way, and it can go wrong in many more ways.