Apple tells a pretty compelling lie here. Rather than execute logic on a server whose behavior can change moment to moment, it executes on a device you "own" with a "knowable" version of its software. And you can absolutely determine no network traffic occurs during the execution of the features from things announced this week and going back a decade.
The part that Apple also uploads your personal information to their servers on separate intervals both powering their internal analytics and providing training data is also known, and for the most part, completely lost on people.