I know it's just an evaluation, but seeing an informal message and a prompt to ask to rewrite this informal message to the tone of an "informal message" when the original one sounds just fine, just makes me sad... Not because of this evaluation, but because it reminds me that this is how some people use LLMs, basically asking it to remove your own voice from texts that are generally fine already.
My sister in law is a pharmacist and the heaviest non-dev ChatGPT user I know and her main use case is writing professionally polite messages to doctors on how the drugs they prescribed to a patient would have killed them had she not caught a particular interaction or common side effect.
There's a lot of "tone" in it as she's not trying to anger these folks, but also it's quite serious, but also there's just everything else happening in medicine.
Feels like a great use.