Why not? Apple's ChatGPT integration has been pretty explicitly anonymizing requests and doesn't require an account. Maybe I'm missing something.

In the article they clearly mentioned that Gemini model will be used for the Foundation Model running on device or their own Server. They are not sending Siri request to Google servers.

You guys use Siri?

Unless Apple is lying:

On iPhone, Settings → iCloud → Storage → Siri → Disable and Delete

Edit: Tried it. It works for me. Takes a minute though.

You're using Siri? lmao

That's the Internet Explorer of chatbots.

You’ve used Siri before?! /j