I'll hazard a guess that they only polled leftist women. Sex is, in large part, about attitude and brain power, and we all know that women on the left just don't have that crucial organ needed for great sex (a brain).
Yes it is about brain power. For women it's emotional too. Men more physical. Men seem to be able to turn it on like a switch. Women need a little more prep work. Not just, a grab here and there and "Why aren't you in the mood?" When a man comes home stressed he wants to release his tension. When I am stressed (usually from little children climbing all over me all day long. I'm not a jungle gym.) I want the closeness, but I don't want to feel like I'm being climbed on again.