From a creative direction perspective, I think this is missing a major part of the story and what's driving much of the slopsign aesthetic.

Your prompts and turns help with the graphic design portion of a poster. But, if you're a restaurant owner, you're doing both the graphic design and the food photography in GenAI, which further compounds the signals of slop that can seem unsettling to someone viewing it.

The former is much more tunable than the latter, but the end diagnosis remains: if you can't tell what's bad in a design, you won't be able to tell what's good, and no amount of turns will iterate towards it. This is one layer above your scope. Art direction encompasses both, because there's a relationship between media and graphic design, especially when you have products to show.