I think you read the exact opposite of what GP wrote.
>By default if her phone rings it should only alert on her primary device. Unless she authenticates to my device at which point everything is there waiting. If her phone was ringing and she picks up my device and authenticates it should answer the call.
He's talking about each person having their OWN DEVICE, but being able to seamlessly switch between devices among their family group.
> Every Apple device, from Macbooks to iPads to iPhones to Airpods is built to be a personal device. (...) Apple doesn’t want to sell one shared device to a family. They want to sell multiple devices to every family member.
Not sure why people are having problem understanding that.