There are a lot of factors to consider. Despite the strong male reader base, I think the majority of the readers are female. So they must be buying into this? These covers sure don't tank. Also the VF man is mostly mature and sort of set in his way, I would imagine. Probably grew up in a world filled with pin-ups. The same world where male nudity was a bit of a taboo.
And yet in spite of it all, the magazine seems fully aware that this irks some readers. There's always a woman complaining in the letters section about the disproportionate showcasing of sex/nudity, but VF try to make light of it by lumping it with other senseless nitpicking complaints.