Not for men (for the most part, as in 99%).
  They either love vagina, and are disgusted by penis, or vice versa.

In ancient Rome, "It was considered natural and unremarkable for men to be sexually attracted to teen-aged youths of both sexes, and pederasty was condoned as long as the younger male partner was not a freeborn Roman." [1]

Most people would agree that genetically, men haven't changed all that much in the last 2000 years or so, which lets us discount the idea that a genetic bit has recently been flipped.

That leaves the notion that sexuality is - at least in part - a social construction.

[1] https://en.wikipedia.org/wiki/Sexuality_in_ancient_Rome