I'll bite

1. Have a user interface. Sometimes I'll ask a question and Siri actually provides a good enough answer, and while I'm reading it, the Siri response window just disappears. Siri is this modal popup with no history, no App, and no UI at all really. Siri doesn't have a user interface, and it should have one so that I can go back to sessions and resume them or reference them later and interact with Siri in more meaningful ways.

2. Answer questions like a modern LLM does. Siri often responds with very terse web links. I find this useful when I'm sitting with friends and we don't remember if Lliam Neeson is alive or not - for basic fact-checking. This is the only use case where it's useful I've found, when I want to peel my attention away for the shortest period of time. If ChatGPT could be bound to a power button long-press, then I'd cease to use Siri for this use case. Otherwise Siri isn't good for long questions because it doesn't have the intelligence, and as mentioned before, has no user interface.

3. Be able to do things conversationally, based on my context. Today, when I "Add to my calendar Games at Dave's house" it creates a calendar entry called "Games" and sets the location to a restaurant called "Dave's House" in a different country. My baseline expectation is that I should be able to work with Siri, build its memory and my context, and over time it becomes smarter about the things I like to do. The day Siri responds with "Do you mean Dave's House the restaurant in another country, or Dave, from your contacts?" I'll be happy.

Isn’t its voice the ui? It should respond using the same context of the request. Voice and natural language.

If you ask for a website it should open a browser.

Edit: everything else spot on