This is what I like to tell people when they tell me they learned something from an LLM:

Pick an obscure subject about which you know a great deal. Now ask an LLM a bunch of questions on that subject and see how long it takes it to give you a wrong answer. Now ask yourself if someone who didn't know the subject as well as you do would have caught that mistake.

Finally, ask yourself: do you still trust the LLM?