> Is it really all that difference from Apple defaulting to Google's search engine?

Not really, because the business model isn't there (at least not in this iteration.

1. The models are Apple models, co-developed with Google. They are not white-label Gemini.

2. There's not currently a Google failover or UX

3. Because of that, there's no user monetization to share.

Apple does have a ChatGPT integration, with failover UX, and with a suspected revenue share deal. However, one could see this deal in a precarious situation, since at the time it started it was expected Apple would not focus much at all on a model capable with world knowledge.