I didn't mention any particular subject when discussing facts and theory. What started us talking about fact and theory though was someone saying it was fact that people are born gay. To which I said the scientific community has said there is no conclusive evidence that confirms this. I didn't make that up. You are free to look it up yourself.
There are some scientists that say yes and some no. But if all are using the scientific method correctly, they would come up with the same conclusion, but this has not happened.
But if you want to talk about evolution, there is no conclusive evidence that man came from apes either. There is a missing link that keeps anyone from calling that fact. There is some evidence that many call compelling, but not conclusive.
The scientific evidence dispels the idea that homosexuality is chosen. You are correct that it does not prove conclusively that no choice is involved.
Human sexuality is largely a social concept as well as biological. It is immensely complex. That is why there is disagreement.
But for the most part the scientific community is overwhelmingly against the bigot's argument that gays choose to be gay. It ain't that simple, bro. Sorry to break it to ya.