Healthcare and law have additional complexities. Both professions have legally protected secrecy, for the sake of the patient/client. Both also have heavy licensing and qualification hurdles. On top of that they have heavy liability burdens in case of mistakes. In medicine for example, review sites like Yelp are a constant source of frustration as healthcare providers have no way of replying or defending themselves against defamation due to HIPPA (there are many cases when prescription drug addicts would threaten and give bad reviews if they don’t get the drugs they want). There is public data on case outcomes, as well as on particularly bad incidents, but that likely also varies wildly by discipline. A doctor willing to take on the toughest cases when others wouldn’t may be punished by those metrics, and still to better by their patient, if they pull doomed people from the brink. If I could have a wishlist dataset it would be for number of particular cases of each surgery or illness a doctor has treated and how many successfully. With Surgeons, especially, those who get the highest volume of cases in a specific discipline are usually the best, and those who do only a handful of a complex procedure per year are likely a danger to the patient. Each discipline likely needs a specialized data filter.

Outcomes are not great for many off these things because they often have poor availability, particularly in quantities that are sufficient to signal quality.

Sure, when a lawyer wins a high profile case, they get more clients, but one case isn't exactly great evidence of quality.