Ask HN: Is Apple Photos using their own AI to tag my pictures?

I recently updated to macOS Catalina. When I opened the Photo app, I was surprised to see a celebrity I had not tagged suddenly appear under the "People" section. I thought only people with 15 or more images showed up under "People", yet I only have one of this celeb. Also, I -never- tagged the celeb.

1. How did Photos tag this person?

2. Why are they showing up under People with just one image?

My only conclusion is that Apple somehow tagged this face using their own cloud AI, and that celebs get precedent.