>Unless one of the models did actually have one eye with eyelashes and one without for the iPhone shoot.

This is just because the eye without eyelashes is on the side of her face that's in shadow. That means there's less contrast between the black of the eyelash and her skin tone (which is darker in the shadow area), and so the denoising algorithm wipes out the lash. All of this image processing happens way too fast on an iPhone for anything deserving the label of 'AI' to be involved. People are just going nuts over the unsurprising artefacts of a completely standard image processing pipeline.