You're misusing this study to make your point. The study is unable to differentiate between fear, anxiety or disgust (all emotions that produce salivary alpha-amylase) and so (as per the study) all it tells us is a group of men in Utah
may experience a physiological response indicative of stress when witnessing a male same-sex couple kissing.
You should really read beyond headlines.
There's also the seemingly contradictory evidence that
gay men are viewed more with disgust than gay women.
There are also many studies that provide counter-evidence. It's not so clear cut. Also "caused" is a strong claim.
However a statistic you must contend with is the fact that an enormous % of childhood sexual abuse exists; a number which dwarfs the % of people who identify as LGBTQ+ which means most abused children grow up to be (or remain, depending on your perspective) heterosexual. 1 in 4 girls and 1 in 13 boys in the US experience child sexual abuse whereas as of 2021 those identifying as queer is less than 6%.
There are also studies that provide bidirectional conclusions. My memory is rusty but back in 2013 a study asked if a prepubescent's sexual identity made them more or less likely to be abused (eg a gay boy/boy percieved as gay was more likely to attract abuse than a heterosexual boy or a gay girl).
A "sane society" does not promote Aryan supremacy. In fact I'd be willing to bet that political extremism and ethno-nationalism produces just as much salivary alpha-amylase enzymes as seeing dudes kissing does.