It's getting less reliable, but look at the details of complex objects. The computational plagiarism engines can't think, and can't do abstract concepts. They fuck up hands because they don't have a concept of "hand" as a category of objects with fingers on the end of arms that grasp things. They're not drawing hands, they're putting pixels where those pixels are statistically probable.

So, look at complex objects - jewelry, buckles, electronics, guns, anything complex. The plagiarism engine doesn't "'know" what those things are. It doesn't know what buttons are or that buckles fasten things together. It's just putting pixels in statistically probable positions. Hence those objects tend to be smears of color and light and dark without actual details. That smearing is still present in many images even as the machines become more sophisticated. The boundaries between things are indistinct and wrong because the machine doesn't "know" what things, objects, concepts, are.