The cited reason given is

> An investigation by the publisher found a number of articles, including this one, with a number of concerns, including but not limited to compromised editorial handling and peer review process, inappropriate or irrelevant references or not being in scope of the journal or guest-edited issue.

It's quite a leap to arrive at AI generated content.

It is all speculation, but it sounds more likely the guest editor did not properly handle peer review (not blind, befriended or non-expert reviewer) and/or misapplied submission selection criteria (maybe out of scope papers by friendly colleagues were not rejected).