Just to reiterate, Apple Intelligence has made only minor updates to Siri. See my post in another thread: Apple Intelligence is wicked stupid! - #6 by ddmiller
Full AI to Siri is coming with to later versions of iOS 18, I’ve heard through the releases into next spring (though there is no official calendar that I know of.) For now we are essentially still using the same Siri we’ve been complaining about more and more for years. I believe it’s confirmed that 18,2 will bring optional ChatGPT integration to Siri requests.