And it stated in the response to the website request that it would do so. So for it to be a fellow IRCer prank, it was a) the LLM's idea; b) only possible because the LLM didn't follow through for whatever reason; and so c) the 'prank' was pretending it did?
Yeah, on second read, I agree with you that IRC chats are not being impersonated. It posted a link (in the PR discussion presumably) to a website where it compiled the report of its IRC interactions in the channel. Would be prankster wouldn't be able to do it.