Because I don't want a Prepear incident of my own (the case record at the US Patent and Trademark Office).
Apple's official guidelines say this:
These guidelines are for Apple licensees, authorized resellers, developers, customers, and other parties wishing to use Apple’s trademarks, service marks or images in promotional, advertising, instructional, or reference materials, or on their web sites, products, labels, or packaging. […]
Authorized Use of Apple Trademarks
[…]
2. Compatibility: Developers may use Apple, Macintosh, iMac, or any other Apple word mark (but not the Apple Logo or other Apple-owned graphic symbol/logo) in a referential phrase on packaging or promotional/advertising materials to describe that the third party product is compatible with the referenced Apple product or technology, provided they comply with the following requirements. […]
Unauthorized Use of Apple Trademarks
[…]
3. Variations, Takeoffs or Abbreviations: You may not use an image of a real apple or other variation of the Apple logo for any purpose. Third parties cannot use a variation, phonetic equivalent, foreign language equivalent, takeoff, or abbreviation of an Apple trademark for any purpose. […]
Under the nominative fair use of trademark law, you may mention someone else's trademark to say that your product works with theirs, but only “as much as is reasonably necessary”. So I may only write plain text like “macOS”, because in theory that is already enough to say what it means, and I can't add an Apple icon to it. But my OCD makes me feel uncomfortable all over without a little icon for decoration, and since even images of a “real apple” are banned, I had to think of something else.
My spare time for this project is precious. I don't want to spend a single moment of my life drawing an icon by hand, only for salaried lawyers to make me take it down and redraw it for a reason like this. But I can't accept the ugly-as-sin plain “macOS” wordmark they require in its place, either. In a case like this, it's enough to let AI make a rough draft, then touch it up a little myself (any fruit will do, as long as its shape has nothing to do with an apple's, so that not even a one-year-old would be misled).