It is true that ChatGPT's answers do not have a deeper underlying meaning because it does not have a consistent model of the world. Many humans don't either. However, it is possible for a chat model to be biased in one way or another. This can happen through human judgment and rating of its answers (as mentioned in the article), or through the selection of the materials it is trained on. So, it is not unreasonable to try to understand its biases because it will be used by students.