I agree the left is dominant in those areas of our culture. I think this is due to the highly concentrated populations of liberals versus the vastly spread out conservatives. And this mechanism is shown in another area of important cultural power: government. I would say liberals and conservatives are pretty equal in this consequential area. I worry about conservatives controlling our governments because I don't think they would try to compromise.
I just watched Pleasantville; another great liberal take on the conservative mindset.