Even Adobes system has questionable training data mixed in
Any prerecorded line having a slight bit of personality to it ("I used to be an adventurer like you, but then I took an arrow to the knee") becomes very noticeable after the first time you've heard it, so the safe thing to do is have lots of the most inane chatter possible ("Nice weather today!") to make it stand out less.
If the game can write new lines and synthesize voices on the fly, you could have more interesting lines without the repetition.
Governments and companies everywhere trying to lock out small time people today before they get too much traction with AI generated content. They know indie devs will never be able to prove their model is only trained on their art. Only massive companies with billions of dollars can do that right now.
Every big company is trying to create rules to ban AI but keep a small enough loophole that they can use it when the time is right.