> social significance of a film (e.g. made by a woman / featuring a woman in a lead role)
for a less divisive example: movies about the film or theatre industry get high marks and fit your example while the audience is left scratching their heads
Excellent point. Critics have often remarked that movies about Hollywood tend to get Oscars just because of the subject matter, which Academy members like.
Also, a less cynical example: some movies are about something new: you might see people who live in a developing country, e.g., Somali fishermen in Captain Philips, or in unusual occupations (e.g., WWF wrestler in The Wrestler). Most audiences just want to relax and not learn something new, but critics love these kinds of movies.
for a less divisive example: movies about the film or theatre industry get high marks and fit your example while the audience is left scratching their heads