A lot of societies have been torturing and killing turd-pushers since the dawn of time. Some (i.e. the societies that didn't have to struggle very hard in maintaining optimal population) didn't. Most societies have now been liberalized to the point where anyone can be openly gay. According to your theory, an island where any sexual deviance was taboo would now have significantly different faggotry rates
vs one where bisexuality was norm
vs one where exclusive homosexuals were tolerated but traditionally didn't reproduce, and that simply isn't true.
People will screw anything that gives them pleasure, and, in absence of faghate, faggotry does seem to work for most people, because it liberates them from the responsibilities of family. History is filled with stories of whole towns "going gay" - which isn't fatal in of itself, but it can be through disease, or if they also largely abandon heterosexual reproduction.
Torturing and killing gays is a basic instinct of civilization. I've heard that Alaskan sled dogs will ostracize and aggress against any dog that's slacking off (which means all the other dogs have to pull harder). Primitive / socialist societies behave the same way toward people who don't work hard enough, but capitalism has largely solved this dilemma by finding more civilized means of encouraging people to pull their economic weight. The matter of demographic weight, however,
still remains unsolved.