I'm not sure, they've been revolving around "AI" stuff for ages; Siri, photo manipulation, identifying people and things in photos (but on your own device), all of which are widely popular. This feels like a logical next step for the path they were on for ages.
It would have been okay if they continued to release features that just happened to use ML under the hood. But instead they are expressedly marketing “Apple Intelligence”, with most of the features released under that umbrella so far not really working well (notification summaries, mail categories, Genmoji, …).
I do wish they continued on this track instead of apple intelligence. I should be enable to click generate audiobook in iBooks and have an audiobook made in any voice of my choosing. Open source solutions are far too slow on macOS, and subpar in other languages.