It's not just patterns like "not just X, but Y", but also deeper patterns and a kind of narrative cadence. Sure it's also mimicking something real, but usually it's a mismatch between the insightfulness of the content and the quality of the delivery. It feels like chewing on empty calories, it's missing the intentionality and the edge of being human. I guess you need to read a lot of LLM output to get a feel for this beyond the surface level pattern matching.
I wonder whether AI house style is the result of the people training it having no sense of writing style or some kind of technical limitation.
With AI, there is no sense of the level of emphasis matching the meaning of the text, or a long-range dramatic arc - everything is a revelation, like somebody who can only speak in TED talks. Everything is extremely earnest, very important, and presented using the same five flashy language hacks.
It was a joke. But also my use of not x but y is not rhetorical but declarative. The whole point is that what many of us are talking about is not simply these surface patterns but how they are used and how the narrative rhythm of the sentences and paragraphs go.