ChatGPT has enough dimensions in its latent space to represent and distinguish between the various meanings of porridge and is able to be informed by the Goldilocks story without switching to it mid-sentence.
It's actually a good example of what I have in mind by saying human text isn't random. The Goldilocks story may not be scientific, but it's still highly correlated with scientific truth about matters like food, bears, or the daily lives of people. Put yourself in the shoes of an alien trying to make heads or tails of that story, you'll see just how many things in it are not arbitrary.