Listening to something that sounds non-human for a long period of time is fairly unpleasant; imagine trying to listen to an audiobook or podcast, or dialogue in

Listening to something that sounds non-human for a long period of time is fairly unpleasant; imagine trying to listen to an audiobook or podcast, or dialogue in an animated movie, when the voices are all obviously non-human/robotic. So TTS wouldn't be usable for a lot of cases where we might want it. And with the way the models work, once you have a model that can sound human, it is unfortunately very easy for it to sound like any individual human as well.