I feel like Apple embracing OpenAI is a betrayal of the trust that Apple has been building up over the last decade around ensuring that your data stays local, or on Apple servers where security is tight. I do not see Apple Intelligence listed on their "iCloud data security overview" page: https://support.apple.com/en-us/102651

It would be hard to imagine your Messages history showing up in Google search results, but ChatGPT just went through that same scenario with their user chats. Also, it used to be common (though I'm not sure how much it has happened recently) to sign into ChatGPT and see other people's chat history in your session. IMHO ChatGPT has not earned any trust.