The original LLM mannerism was the use of the word "delve".

The second one was the use of em dashes.

The newest one is the "it's not X, it's Y" pattern.

To be taken seriously as a writer, it's better to avoid these mannerisms. Otherwise, you'll be accused of being an LLM.

This is some kind of reverse Turning test, where the human is trying to *not* sound like a machine, instead of the machine trying to sound like a human.