This was approached all wrong. The first highly publicized demos of singing generated like this should have been of dead people - Michael Jackson, John Lennon, Elvis. First, it's not clear who has the right to sue, and in what jurisdiction. Rights associated with those people have been transferred and resold enough times that there's no clear claimant. Second, many people have impersonated those voices, so there's a strong argument that this is just automating a manual process. Someone could have probably gotten a few tracks out the door and onto airplay before the first litigation.

Going up against a living performer whose main asset is their vocal style makes a weaker case. Living people have stronger publicity rights than the estates of dead ones. This could result in a decision which expands the scope of copyright. One of those weird copyright decisions, like the one where Owens-Corning trademarked PINK, as a color, for insulation. Coloring insulation was so unusual that it was held to be a valid trademark. Now there are other copyright on colors. Bad cases make bad law.

This thing has been botched so badly that one wonders if it's a fake case from the music industry to get a losing decision.