No - there is a huge difference between "this AI created this image" and "this user did it" - the first we need more of, and the second is a big privacy concern. The article does not say anything about identifying a user.
so unless you want to draw a distinction between 'user' and 'machine' , yeah it is for identifying users.
to believe otherwise, especially with Microsoft involved, would be incredibly naive to their history.
Microsoft GDID telemetry includes full browsing and gaming history https://news.ycombinator.com/item?id=48787239
"I haven’t read enough to understand". Oh, now I know the answer to my question