Before homosexuality was culturaly normalized there were a number of studies explaining it, like any other decease.
Manliness it an integral part of male human. If one is rejecting it that means he really despise himself, a masochist and overall a self-destructive person. You should expect suicide from them.
Many males teens in the US of this generation are feminized and have acquired many of the traits considered indicators of homosexuality in previous generations. You can see it everywhere in the US. So many of them never acquire deep voices and they use feminine mannerisms. Emotionally they are more similar to young women than to their fathers. Part of this is the social indoctrination they get from birth, so it is more obvious in young males from liberal families but I think another part is hormonal which makes them receptive to being more feminine. Inadequate amounts of testosterone and too much estrogen being produced in young males. Early puberty in females suggest something is different compared to past generations and affecting males as well.