[prashnts]

Quick observation from the data presented in article (very well done, by the way): Beginning iOS 11, if I remember correctly, Apple finally added the ability to delete stock apps. Deleted apps could be downloaded from App Store later. Perhaps the « boost » in search rankings for the stock apps was related to that ? If the dates match, I assume they would have wanted these to be found easily and screwed up in scoring. This is assuming good faith, of course.

Edit: I did not remember correctly! This feature was added in iOS 10, released in September 2016.