I don't think the cover displays that women are just sex objects and men are all hulking beasts. He IS a hulking beast, but he is a Dragonborn, kinda comes with the territory. Also, while she does show off a bit, she is far more dressed than many of our historical D&D examples of art. She also looks like if you tried to call her Toots and grab her ass she would melt your face off.
I admit she's an improvement over Larry Elmore's typical fare, but Larry Elmore is the poster child (pun intended) for sexist fantasy art, so that isn't saying much. She's still got breasts bulging out of a top which is apt to have a wardrobe malfunction next time she takes a deep breath. The pose isn't too bad, but it's still clearly calculated to show off her breasts and butt - look at the way her torso is angled, and compare it to the dragonborn's. And she's proportioned like a porn star.
I have no problem with sexy women on the cover of the PHB, but as I said before, there's a difference between
sexy and
sex object.
As far as the "hulking beast" thing goes, I don't have so much of a problem there. I don't think the dragonborn is playing to male stereotype particularly, I just think he looks stupid.
I also don't see what is the problem with wanting to be that guy. You're trying to get people interested in the game. For many people, they get a good shot of how cool someone looks and decide they want to do that.
Nothing wrong with that, but I would never in a million years want to be
that guy. He looks like a Teenage Mutant Ninja Turtle gone horribly wrong. I
might want to be the tiefling in the other picture, after tail removal surgery.
As PPaladin points out, the Character Record Sheets picture would be quite a lot better for the cover of the PHB. I still don't like Wayne Reynolds's cartoonish faces or his lurid color palette, and the female character's pose is still off, but she is at least reasonably clad (I think - the scan is too low-res to be sure), and the scene is exciting and engaging.