Isn't it as a lot of 'horror' based around the conflict between our Apollonian and Dionysian traits? The majority of the film is meant to put us on the side of the islanders, as Woodward is portrayed as a prig, and a hypocritical one, before the reveal is that the Dionysian unchecked leads to the murder. The reaction of those complaining is precisely mirroring Woodward.
As the Dean's comment makes clear, sex and connection to the earth are not antithetical to any god, unless you're a Manichee, rather they are part of what was created and attempting to cut them off entirely as evil is unbalanced. Too much religion stops discussiin, so points to Derby.