Neither Apple's nor Google's announcement says Siri will use Gemini models. Both announcements say, word for word, "Google’s technology provides the most capable foundation for Apple Foundation Models". I don't know what that means, but Apple and Google's marketing teams must have crafted that awkward wording carefully to satisfy some contractual nuance.
Direct quote from their joint statement: "Apple and Google have entered into a multi-year collaboration under which the next generation of Apple Foundation Models will be based on Google's Gemini models and cloud technology. These models will help power future Apple Intelligence features, including a more personalized Siri coming this year."
> "Google’s technology provides the most capable foundation for Apple Foundation Models"
Beyond Siri, Apple Foundation Models are available as API; will Google's technologies thus also be available as API? Will Apple reduce its own investment in building out the Foundation models?
I see what you mean, though I think “these models” refers to Apple’s Foundation Models, which “will be based on Google's Gemini models and cloud technology.” I guess it depends on wrist “based” means.