The economics of AI still seems nuts to me. Feels like another bait and switch in the making when all these "free" services need to start showing some revenue.
The direct interactions with AI increase the fidelity of the customer model of you that Google has and uses to optimize sales to you for it's customers.
Even further, the most common source of inspiration for purchases is the behavior of other people. If the AI can sufficiently emulate humans and ingratiate itself enough to you then it can directly influence your behavior just by suggesting that it would make certain decisions in your place or that others have already.
This is actually not far removed from the existing situation, just the next level of technological capability.
By actually generating responses for you, it starts training you to allow it to make decisions on your behalf. This may readily extend into purchase decisions.
GPT: “You can buy {x} product. Would you like me to put it on your card? It will arrive in two days.”
Human: “Sure!”
This is what Google wants to control.
With how humanity is going so far with the ad driven web, outlook not so good.