Earlier quoted context omitted.
From a user perspective it's 100% clear. If the system doesn't say "I'm gonna phone a friend to get an answer for this", it's going to stay either 100% local or at worst 100% within Apple Intelligence, which is audited to be completely private. So if you're asking for a recipe for banana bread, going to ChatGPT is fine. Sending more personal information might not be.
Still involves friction. A more "seamless" way for Apple to do this would've been to license GPT-4's weights from OpenAI and run it on Apple Intelligence servers.
I want to use perplexity from siri too!