I was familiar with that phrase and its shorthand ("GLHF") but the latter half of the sentence ("for interacting with GPT models") confused the punchline enough that the joke just didn't land, because the context is one of using RL to "interact with GPT" (relevant to this article) but a more appropriate context would have been regular ole RL using agents in a simulated environment, like - I don't know, a video game?
Maybe I'm overthinking it though.