They are definitely capable of writing such statements, which you can see in their enterprise products. In my Google Workspace gemini app it says pretty prominently and clearly:

  Your [ORGNAME] chats aren’t used to improve our models

So they definitely understand that people want to hear that their data isn't being used for training, and they know how to say it clearly and reassuringly. Which makes the omission of that in their consumer products more telling in my view.

Haha, but do they paraphrase your chats, and use it for training? (Ye$)