The "power fantasy" for videogame is either a myth or an evidence.
Videogames tend to despict you as all powerfull and flatter your ego, but that's not why they strip male character.
The idea of male nudity being different from female nudity come from "privilege" as seen by the Americans : instead of being a set of tangible advantage deliberately set in place to profit to the elite, it became an intengible notion supposedly helping certain part of the population (which is very convenient for said elite, suddently barely more privilieged than an able bodied rednek).
Male nudity therefore has to be different from female nudity and it resulted in the rise of that concept : males weren't sexualised, they were the realisation of the "power fantasy" of the player.
It seems pretty obvious to me that men on the cover of romance novel are really, really buff, or that the American-style ultra muscled nearly nacked hero come from a fetish author, or that the physique of Twilight's cast require hours in the gym and a special diet, and therefore that muscle are sexual attribute too.
Another argument is that it's not designed for women, but I don't think that it have to be. Women don't need videogame tailored for them, and those I know either play them sometime or have a passive interest for them. Simply put, they are expected to have other hobbies, and simply do that : series have a pretty mixed audience, and I'd be really interested to know the difference between the two.