ok, here is what I don't understand, and it goes beyond this, so I won't use the term gay or homosexual.
if you as a human were genetically or mentally inclined to be one way, whether you liked the taste of meatloaf, liked the color blue, or found chick flicks stupid, and there was a pill that would and could reverse any of those dispositions without side effect and without "physical memory", that is you would never miss liking the color blue because you just won't like it any more, you like red now instead and that is just the way you feel, what would the impact be?
To speak directly to this topic, the question remains the same. if a gay person were to "take a pill" and truly not be gay afterwards; no homosexual feelings, no emotional or sexual attraction to members of the same sex, would there at all be any regret for no longer being gay if that just isn't how they feel anymore? and by way of transitive theory, the same could be asked of straight people. if they were to take a pill to be gay, and just held no interest afterwards of being straight (without any of the emotional issues with typical bigotry that can happen towards a gay person), what would the impact be?
it also goes a small ways towards answering the question on if it is a choice or not, because in this case someone would have the choice, literally, and the complete control over making it.