You need to keep an open mind while watching this documentary. Remember that people are just stating their opinions, and try to value them. I personally did not agree with all of the statements or world views portrayed, but still think it's important to hear them.
Unfortunately it is very easy as a guy and especially if you are a gamer to become infuriated by some of the arguments (or the mere sight of Anita Sarkeesian). But if you are able to get past that you might actually discover that there are many valid points being made.
I love gaming and video games and I think everyone should be able to enjoy them, man or woman. I would hate to be told I cannot do the thing I love because of my gender. That is why I think people should give this film a chance. Perhaps next time you meet a female gamer in lobby or forum you will think twice before casually making a sexist joke or comment.