Do you mean

(1) "this diagram was created using an AI system, but I'm saying nothing about whether it's actually accurate or clear or useful or insightful"

or

(2) "this diagram was created using an AI system, and unsurprisingly it turns out to be ugly, riddled with errors, and not actually to convey any information useful to humans"?

I think it's more useful to reserve "slop" for the second of these. Even if it's true in some domain that the only thing AI systems can make are "slop" in both senses, they might improve.

(I'm not saying that there shouldn't be a way to say the first. I just think it shouldn't be "slop" because that word is valuable as a way of saying not just "AI-created" but "AI-created, and bad in the way that many AI-created things are at the moment".)

Note: my question is a genuine question; I don't know anything about Immich and can't readily tell just from looking at the diagram whether it's actually accurate and/or useful. So I can't tell whether #1 or #2 is the actual meaning.