So I could write a song, and get ...oh, lets say, a sample of Celine Dion's voice and using this technology, have her voice singing it. Or, for that matter, any other singer in the world. I'm thinking their lawyers would be in touch pretty quickly on that matter.
Do you (or anybody else) remember the Fairlight CMI? It was THE thing back in the 80s. At the time they started at $25,000 so not many of us had one, but inside that Computerized Musical Instrument (CMI) you had the ability to do exactly that. You could sample a voice and it was able to take that voice sample and make it become a synthesized voice that would sing anything you could play into it, AND it had the ability to read what you typed it. I think they were Australian and the cost hurt them, but I know Peter Gabriel did one whole album with a Fairlight and a Linn drum machine. There was a studio in Cleveland that had one and I booked an hour of time just to get a demo of the Fairlight. And the guy who owned the place, Bill Cavanaugh, ended up showing it to me for almost 3 hours and didn't charge me at all.
So this is not new technology. That doesn't exclude the lawsuit angle, as I assume the estate of Elvis Presley would probably sue the pants off anybody who released a new Elvis album with synthesized vocals....