https://musicbrainz.org/doc/Label has not been updated since we replaced Countries with Areas.
I've noticed many editors have been editing labels to use the area where the label is headquartered. I propose a guideline similar to what we have for Artists, where the main Area is the country where said artist is mainly active. I do realize with Labels there's no "begin area" field like there is with Artists; the solution I envision is an Area-Label "headquartered in" or "founded in" AR.