Deciding whether A is an X or a Y is a really basic part of why we're all communicating. Suspicion of em dashes is one thing, but once you start getting nervous on seeing "It’s not X. It’s Y." then you're just going to get paranoid.
The fundamentals of an LLM is to statistically match their output with the corpus. The tics they have are really common in natural human usage too.
Did you read the article? It's all AI tells. The tone may as well be a fax machine
This line of argument would fall down if it turns out that a human with statistically normal output is a bizarre-sounding human.