Which version though? 3.5 or 4? It does not state this explicitly. There is a world of difference between 3.5 and 4.
I personally had seen good and bad parts of diagnosing with ChatGPT 4, and what I would interested in is if the doctor tries using multiple questions and finds out how to use the tool well.
I believe he could have improved the tool significantly if he puts in the time to experiment with it.