When I see an image, it's really easy to tell it's A.I. generated, even with no "anomalies".
It's so many things. The lack of composition, the inconsistencies, the lack of artistic direction and story. As a random case study, with the popularity of "Ghibli style A.I. art", when humans made one of my favourite films Arrietty, each scene has emotional direction and a purpose. An A.I. will never be able to convey the melancholy look of a disabled character, or contrast it with the joy when they finally make a friend. Or the grim determination to protect something important to you.
They can't make artistic decisions or put in details or foreshadowing. Nothing will surprise you and make you think, "oh of course they need this improvised tool to exist in this tiny world". It won't make you laugh or cry. Because there's nothing at all "behind" the image. No thoughts or life experience or emotion. It's just a statistical average based on a prompt. But it might look decent enough to survive a cursory inspection.
I found these examples from a quick Google search to compare A.I. with genuine Ghibli. Surely you can tell what mean with these.
No worries, it's more of a gut feeling than anything specific. I'm not really looking at the picture with a microscope. It's more, immediately when I see the overall image I'm like, that's A.I. I almost feel a twinge of sadness or disappointment when I see A.I. images now, like I'd rather there be no image at all lol