At what point did Claude fail with that, generating a list of events from the scan, or adding the events to the calendar?

I had a different AI (Grok) successfully take a prompt like "I live at this address and need to pick up my son from school at 2:30pm, and then we need to hit these three stores before heading back home. Find the path with the least driving and add all of these as discrete events to my calendar with their addresses embedded, and give me a google maps link with the full path so I can double-check". Did it correctly on the first try. I'd think other AIs could do that too. So I'm thinking it was the scanned image that gave it problems?

If you had done this on a Mac, it would have worked just fine. The failure in your chain is iOS Calendar not being an intent handler for ICS files.

Another way you could have solved it would be to have the Google Workspace connection set up in the backend for Claude and it would write the parsed events to your account directly. Then in iOS you could move the events to the iCloud Family Calendar.

Or again, if you did this on a Real Computer, you could bulk-move them.