If the creators set the LLM in motion, then the creators sent the letter.
If I put my car in neutral and push it down a hill, I’m responsible for whatever happens.
Additionally, since you understood the danger of doing such a thing, you were also negligent.
Rob pike "set llms in motion" about as much as 90% of anyone who contributed to Google.
I understand the guilt he feels, but this is really more like making a meme in 2005 (before we even called it "memes") and suddenly it's soke sort of naxi dogwhistle in 2025. You didn't even create the original picture, you just remixed it in a way people would catch onto later. And you sure didn't turn it into a dogwhistle.
I merely answered your question!
> How can you be grateful enough to want to send someone such a letter but not grateful enough to write one?
Answer according to your definitions: false premise, the author (the person who set up the LLM loops) was not grateful enough to want to send such a letter.