They're listing the use cases where a 10-20% hallucination rate isn't a big deal. They can't advertise the truly useful applications of the tech because it's not reliable enough (yet).
But they can make it more reliable over time by deploying the product now and training on user data:
> Google collects your chats (including recordings of your Gemini Live interactions), what you share with Gemini Apps (like files, images, and screens), related product usage information, your feedback, and info about your location. (...)
> Google uses this data, consistent with our Privacy Policy, to provide, improve, and develop Google products and services and machine-learning technologies, including Google’s enterprise products such as Google Cloud.