On the other hand, I have multiple minor issues where doctors have not been able to offer a diagnosis (they just say "I don't know") and ChatGPT has been able to offer multiple possible diagnoses.
"I don't know" is exactly what I want my docs to say when they don't know.
Right. And going forward, if they take help from ChatGPT they will have to say that less often.
Do you really though? Wouldn't you want them to say "I don't know, but here are the next steps I think we should take to continue getting to the bottom of this (further tests; the doctor reviewing literature or consulting with colleagues; a referral to a different specialist etc)"?