"All entities except place, release, and series support: ratings, user-ratings" (https://musicbrainz.org/doc/Development/XML_Web_Service/Version_2#ratings)

Place reacts to a ratings request by erroring: "ratings is not a valid inc parameter for the place resource". So does Series. Release reacts by ignoring the ratings request, but not erroring. Area officially supports ratings, despite them not actually having a rating option: they probably should also error instead.