This article summarizes it well: How Might Homosexuality Develop? Putting the Pieces Together.
The growing number of former homosexuals raises some serious issues with those pushing the genetics angle.
I'm not qualified to argue this subject. Husband is and he strongly disagrees with the studies you have cited. Bogus. Try researching male twins.
When he was in medical school, a facility in Great Britain claimed to have cured homosexuals. He looked into it and found that not one had been cured of homosexuality. The reason? It was a chioce of saying they were cured or prison time. They took the treatments, then went back to homosexuality.
Before it was popular to come out of the closet, homos who married were only able to fulfill their 'duties' by pretending they were having sex with a male.
The sexual urge in humans is strong., one way or the other, and rarely both ways.