Why do AI images look the way they do?

Specifically, a lot of AI generated 3d images have a certain “look” to them that I’m starting to recognize as AI. I don’t mean messed up text or too many fingers, but it’s like a combination of texture and lighting, or something else? What technical characteristics am I recognizing? Is it one specific program that’s getting used a lot so the images have similar characteristics? Like how many videogames in Unreal 4 looked similar?