I think you are just wrong about that.
I don't think sex is dirty but I do believe that there is language that may be OK in the locker room that I don't choose to listen to in front of my parents and grandchildren. The F word happens to be one of those words. Hollywood thinks it sells. They may be right but not in my case. I don't buy their movies with foul language in them and I don't watch them on television either. This is just a piece of my problem with Hollywood - they have given up story telling in favor of car chases, explosions, simulated sex, violence and foul language. If story telling was still the goal, a little of the latter would go a long way instead of being the focus.