Right. I assume that Gunn was not limiting his choices to DC in theory, but in practice, he has pretty good reason to promote the brand.Not All Robots by Mark Russell & Mike Deodato Jr. would probably be my pick, though that's not DC (but he did say "favorite comic book of 2023", not "favorite DC comic book of 2023").
Still, The Human Target is off-the-charts awesome. Have you read it, Kai, and if so, what did you think of it? I haven't read Not All Robots, so can offer no opinion there -- though I have liked some of Russell's other work. Superman: Space Age is flawed but ultimately very moving, and the first half of One-Star Squadron was among the funnier comics I've read in ages (though for some reason Russell seemed to abandon comedy almost completely in the book's second half, to my disappointment).