Perhaps the feeling of power stems from the fact that the ladies tend to find a nicely chiseled man to be sexually attractive. I'm just sayin', from experience, the ladies do have a habit of admiring a man with that look. I know, because I have nothing like that look irl and I hear girls going on about dudes with that look all the time. It used to get to me a little, but I got over it because confidence as ever remains king. The other argument I have towards the power fantasy thing is that many of the characters in FFXIV who choose to show off their chest in FFXIV don't choose the Roegadyn race, which is (as demonstrated by The Bulge) the most physically powerful character in appearance. However you see Lalafell, Miqo'te, Hyur and Elezen males all showing off their chest, so... See also: Wolverine. Small guy. Shows off abs. Girls go gaga for Hugh Jackman.
I would certainly say it has a lot to do with sex appeal. It's possible that you're only looking at it from the perspective of someone who just doesn't find that kind of thing sexually attractive. In the end, I've found that girls do most certainly like a nice chiseled man's chest, arms, buttocks and legs. Some might like other things, but I hear about these things a lot. I'm not including faces in this because both genders find it apparently completely okay to be intoxicated by the face of someone else as if that's somehow less shallow than other parts of their body. *dunno*
In the end, it's important that a person can distinguish between appearance and personality. I can appreciate these things seperately pretty well. If a girl is physically attractive but an absolute horrible personality (that sounds so harsh, honestly) then I would not be very attracted to them overall.
I do still see the sexualising going on in games (and film!), but for me it's all down to whether or not you think someone is capable of enjoying a sexy looking character without it somehow damaging their ability to appreciate other people for who they actually are in the real world. The problem is in the individual if they can not do that. If they can't do that, then... well... yeah.
