interesting test case
There's been a ton of talk over the past couple of years that there aren't many good movies starring older women anymore. It was even addressed in an acceptance speech during the Oscars this year. Now we've got a film written, directed by, and starring a woman in her late middle age and it's subject matter is about familial relations and rediscovering yourself later in life - two subjects that should have mass appeal for older women.
My guess is that it won't be on a ton of screens, but a fair enough amount that it should get word of mouth, if there's any to be had, and a small enough number that if there is an underserved audience out there then the $/screen should be a decent amount. That in turn should generate a desire on the part of investors to duplicate the movie's success.
If the movie is successful, but it's not followed by a number of copycats then the critics out there will probably have a point. If it's successful and there are a lot of copycats and they're also moderately to wildly successful, then the critics' complaint well have been affirmed. If the movie is a flop then the critics' argument will take a hit. Their argument can't be dismissed outright, based on one movie, but it will be hard to keep arguing that a lack of older women in film is some kind of injustice if there really isn't an audience for their stories.