I find it reasonable to think that people can broaden their sexual interests over time somewhat like their experience of foods, arts and even work. I think there is a knee-jerk reaction to "acquired homosexuality" because it was used so long a an excuse to persecute homosexuals. But like many arguments in our society, I think it is the wrong hill to die on. Because to overly concern oneself with winning the argument…
We, both legally through government and as a societal standard, should not be discriminating about what people do (whether its sexual, religious, or whatever), regardless of their internal motivations.