The other very real aspect here is "training data" has to come from somewhere, and the copyright implications of this are beyond solved.
In the past I worked on real algorithmic music composition: algorithmic sequencer, paired with hardware- or soft- synthesizers. I could give it feedback and it'd evolve the composition, all without training data. It was computationally cheap, didn't infringe anyone's copyright, and a human still had very real creative influence (which instruments, scale, tempo, etc.). Message me if anyone's still interested in "dumb" AI like that. :-)
Computer-assisted music is nothing new, but taking away the creativity completely is turning music into noise -- noise that sounds like music.