However the other day I asked the Gemini assistant on my phone to check the birthdays in my calendar, get all their dates, then make a graph of how many fall in each period with a 15-day moving average. It did everything as instructed including writing a python script to generate the graph, then discussed the results with me :)

I would expect Siri to be able to do anything on the iPhone that I can - change settings, report stats, kill/launch apps, etc.

It would be nice if it could control 3rd party apps too, like GMail, but being able to control the stuff that Apple themselves have built doesn't seem a lot to ask.