It's not just a random "voice for your chatbot", it's that particularly breathy, chatty, voice that she performed for the movie.
I would agree with you completely if they'd created a completely different voice. Even if they'd impersonated a different famous actress. But it's the fact that Her was about an AI, and this is an AI, and the voices are identical. It's clearly an impersonation of her work.
It's not just a random "voice for your chatbot", it's that particularly breathy, chatty, voice that she performed for the movie.
I would agree with you completely if they'd created a completely different voice. Even if they'd impersonated a different famous actress. But it's the fact that Her was about an AI, and this is an AI, and the voices are identical. It's clearly an impersonation of her work.