As an aside AP Style is not use an Oxford comma, and that's been the rule for 50+ years https://www.prnewsonline.com/explainer-how-to-use-oxford-com...

This is upsetting.

Yes, finding out how badly wrong you were is never fun. Of course the lack of ubiquitous Oxford comma use is itself and separately displeasing.

AP Style is simply wrong on this, then.