Just like others in this thread I am not a big fan of the label "homosexuality". Historically its a very new word, which did not exist when the Quran was written. The Quran talks about the action of having sex with someone of the same gender. It does not say that these actions define these people and turn them into "homosexuals".
However, I saw that you defined homosexuality as "the state of being sexually attracted to people of their own sex". So from this definition we can discuss whether it is a sin or not.
It is not a sin to feel sexually attracted to people of your own sex! I have even had sunni scholars tell me clearly that this is not a sin. You can not control who you feel attracted to, so there is no sin. You are right that it is not a personal choice, just like a socalled "heterosexual" (another word I dont like) can not decide which women he wants to be attracted to.
I dont understand your need to find out if its a personal choice or not. The Quran does not say that its a sin to feel sexually attracted to someone of the same gender, and as mentioned even many sunni scholars agree with this. You seem to meet the wrong kind of religious people.
However, the Quran is very clear that THE ACTION of having sex with someone of the same gender as yourself is a sin! That is what is a sin. It is not the feeling of being attracted, or the desire that is a sin - it is the action. Having sex with someone of the same gender is a sin.
This is clearly written in the Quran. It should also not come as a surprise to us, since it is in general clear in the Quran that sex is only allowed when you are married, and a man can only be married to a woman. A marriage is a "permission to have sex" and 2 men can not get this permission.
"Homosexuals" are normal people, and just like other people they have a personal choice in what actions they do. If they have sex with someone of the same gender, then that is a choice they have made (unless they have a brain tumor...). And it is a sin.
It is not different than a "heterosexual" man who feel attracted to his neighbours wife. If he chooses to have sex with her he has committed a sin. If he choose not to, then he has done a good thing. When we abstain from those of our desires that go against Allahs rules, we do a good deed.
There is no scientific data in this post. Because the thing that is not a personal choice (the attraction) is not a sin, and the thing that is a personal choice (the action) is a sin. So I dont see why you need to discuss whether the first is a personal choice or not. It has nothing to do with the ruling that the action is a sin.
There is evidence showing that homosexuality has existed long, long before the people of Lot.
Can you please provide this evidence?