My experiences over the past few years is that girls in their early 20s want to be dominated, and even manhandled. These girls want to be fucked hard, with agression, spanking, choking, etc... As I reflect back on it I am not sure if girls were like this in college, or that I was not experienced and confidant enough to understand what they wanted and deliver.
Also younger women tend not to be as vocal before hand in what they want. They tend to be shy, or are worried that their partners will think they are "slutty" - which of course to me is a compliment.
I doubt this says anything about general society, it is probably more to do with the circles I run in.
Since I do not get much experiences with older women ( over 30) I think I am missing out on what Serge describes above as POWER. It gets boring after awhile of always being the dominate alpha male in the bedroom. It is the roll I play in the real world all the time, and could use a break!!