Using a robotic voice could make the game more accessible to blind, partially sighted, and dyslexic individuals. I’m not sure how an AI voice is inherently different than the voice that comes out of a screen reader, especially if it’s trained on the voice of employees or volunteers.
What about partially sighted or dyslexic individuals? Sure, a game like halo would need a lot of modification to be fully blind accessible, but a visual novel, for instance, might not. In my experience most visual novels are built as passion projects on shoestring budgets.
Lots of existing games have robotic narrators already (e.g minecraft), they just speak with a monotone voice. By incorporating more advance machine learning capabilities the same narrator could be capable of outputting a more nuanced and pleasant delivery for those that need it.