I think it is clear that if Apple were going to deal with OpenAI on that level, they already would have. What they wanted for their AI products is a measure of control over their destiny that OpenAI clearly did not want to give them that badly. It's also pretty clear that Apple is willing to work with arch-rivals to supply components of their products, both software and hardware, but values consistency alongside trustworthiness.

This stuff happened years ago, right? Something tells me that discussion has already happened, and they went with Google.

Besides: Apple is a "real" company that will definitely still be around in five years. They've already fumbled Siri multiple times. IMO Google was certainly the right choice for actually executing well on Apple's own terms for the foreseeable future.