Compared to IBMs Steven Hawking's chair, maybe. But apple tts is not acceptable quality in any modern understanding of SotA, IMO.
If you need a not-visual output of text, SoyA is a waste of electrons.
If you want to try and mimic a human speaker, then it ain’t.
Question is why would you need to have the computer sound more human, except for “because I can”.
We can't be friends
I think translation would be a big use - maybe translating your voice to another language while maintaining emotion and intonation, or dubbing content (videos, movies, podcasts, ...) that isn't otherwise available in your native language.
Traditional non-ML TTS for longer content like podcasts or audiobooks seems like it'd become grating to the point of being unlistenable, or at least a significantly worse experience. Stands to benefit from more natural sounding voices that can place emphasis in the right places.
Since Stephen Hawking was brought up, there are likely also people with voice-impairing illnesses who would like to speak in their own voice again (in addition to those who are fine with a robotic voice). Or alternatively, people who are uncomfortable with their natural voice and want to communicate closer to how they wish to be perceived.
Could also potentially be used for new forms of interactive media that aren't currently feasible - customised movies, audio dramas where the listener plays a role, videogame NPCs that react with more than just prerecorded lines, etc.
There's a lot of stuff I don't have time to sit down and read, but want to listen to while I cook/laundry/shower/drive/etc.
Often recordings don't exist. Or when they do, an audiobook just has a bad voiceover artist, or one that just rubs you the wrong way.
The more human text-to-speech sounds, the easier and less distracting it is to listen to. There's real value in it, it's not "because I can".
You know how it's nicer to read in 300 dpi instead of 72 dpi? Or in Garamond rather than Courier? Or in Helvetica rather than Comic Sans? It's like that, only for speech.