an AI-generated comic lost its copyright protection because the USPTO determined that "copyrightable works require human authorship."

From the comic's website:

For the first time the millions of writers who have seen worlds and characters in their minds can now bring them to life on the page. The promise of a new, real-time creative tool for story development and creation is here.

So there is human authorship here. And not only in the sense that someone "used a tool to generate an image"; they created a story, generated images to fit that story, and assembled the images into a comic. This isn't an "AI-generated comic," this is a comic featuring AI art.