Fortunately for Scarlett, she can just sue them and force them to tell her. She also isn’t shy to litigate. I was surprised that Sam wanted to poke that particular beehive.
Voices such as Shatner or Walken are at least as much about speech patterns than the voice, giving you another axis to compare voices against, so I can somewhat see those as being trademarkable. But when I hear the ChatGPT voice, it just sounds like "slightly-flirty generic female voice 03" to me.