I thought it was underwhelming. The fact that integration with ChatGPT is not seamless pours cold water over it. Siri will seek your permission each time before passing the question to ChatGPT. I can avoid that step by using ChatGPT directly.
I do agree that the extra tap is a bummer for anyone that wanted ChatGPT baked into the OS, even easier to access than it is in the ChatGPT app.
I am not entirely sure I will ever actually allow it to connect to ChatGPT for privacy reasons, but having the option when it can't be handled another way is nice.
I imagine this is more a stopgap until more and more of this can happen locally anyways. Especially since it sounds like Siri determins when it should reach out.