It’s legal to publish anonymous patient data, doctors do it frequently e.g. in “case studies”. As long as it can’t be traced back to the patient I don’t see why they should care (I wouldn’t). And since it increases public knowledge (e.g. how to treat future patients) I think it’s not only ethical, but should be encouraged.

Doxxing also increases public knowledge, but knowing who’s behind some online pseudonym is much less useful than patient anecdotes (what would you do with the former? Satisfy your interest (or what else do you mean by “public interest”)?). Moreover, unlike anonymous patient data, it has a serious downside: risking someone’s job, relationships, or even life.