The technology was created to replace voice actors. That’s the actual purpose. Its very existence hurts their profession and benefits studios. You can not be a studio, use this technology, and claim to care about ethics, anymore than Amazon can claim to care about the workers as it invests in the machines to replace them.

It doesn’t matter if you compensate or get their approval, because the fact is the existence of the technology in the industry effectively compels all voice actors to agree to let it use their voice, or they can’t get work. It becomes a false choice.

If there was no financial benefit, if it truly made no difference in how much a studio pays in labor or the amount the artists make, there would be no reason for studios to want to use it.

Do you have any source for those claims? There are plenty of better reasons to develop voice synthesis than replacing voice actors.

Voiced characters that use generative AI in real time instead of prerecorded lines and a dialogue tree come to mind as an obvious use. How cool would that be, to be playing an RPG and ask any character any question you want and get an actual verbal answer? No way you can do that with voice actors.