Aphantasia doesn't seem relatable to me at all. I certainly can imagine mental pictures at will, even pretty detailed ones if I try really hard. What I certainly can't do is to recall a picture I've seen "in its entirety". I can imagine Mona Lisa and somewhat describe how it looks like, but I can't recall many things about it - like the actual background behind her head or the way her hands are placed. I can only make it up based on some clues I remembered (for example: I remember a popular novel describing Mona Lisa's background as being higher on one side and lower on the other, but which one was it?)

Now, if I spent many days studying Mona Lisa with intention to memorize it, I would probably be able to recall it "in its entirety", maybe even sketch it pretty well - but the same would apply to an essay.

Maybe the author actually has hyperphantasia instead?

Same. Even when I dream. The images I see aren't complete images but ideas, or very staticky halos of what it might be. When I dream about, say, shopping in a mall.. I don't actually see the mall or myself or anyone at the mall, but dream the idea of the mall. None of the visual details are available to me.

Never knew other people didn't have the same thing until very recently for me. It was eye-opening.

I, too, am an aphant (which I believe affects only 3 to 10 percent of the population), but I understood this to still apply to us: the picture is merely replaced with the small kernel of a concept it represents.