Despite seeing a lot of them, I cannot think of one AI-generated photo that I can picture clearly in my mind; a few are partial but elusive. Whereas I can recall (visualise) a whole bunch of traditional photographs.
The same is true of AI generated text. Only the annoyances stick. I cannot recall real details of text I have generated, until I commit it to memory some other way.
I don't think this is about ephemerality either. If we assume it's about celebrated/famous/infamous images, there are definitely non-ephemeral, cultural moments in AI generated images in particular, like Boris Eldagsen's Sony Prize winner:
https://petapixel.com/2023/04/14/artist-refuses-prize-after-...
This really should be memorable, but isn't. I had forgotten the second person is in the image.
Or Jason Allen's fake painting:
https://petapixel.com/2022/09/01/ai-generated-artwork-wins-f...
I had already forgotten there's more than one figure in it, and I only looked at it a few weeks back. I remember the colour, the bright circle, some vague hints of texture; one figure. And that is it. Only the crudest shape elements.
For me, something about AI-generated text and images confounds recall. It is really peculiar.