Ancient Greek culture was noble, glorious, and was fine with gay people in certain contexts.
But there is one reason why being "gay" as a lifestyle is bad. Well, one good, iron-clad reason that cannot ever be defeated:
Gay people fail to pass on their genes, and thus they make the difficult quest of survival and reproduction of every single one of their ancestors pointless. Being gay and not breeding is an insult to every ancestor you've ever had, throughout all life itself.
There are certainly other reasons to not be gay, but those are less philosophically vital than this one.
However, in this dark age, there are not enough breedable women for all the men, so some men will have to simply die alone. There is no way around this. Thus, gay men take two men out of the population, and gives the rest of us a better chance. Then the two gay men can be happy, and the rest of us can actually breed with the few remaining women that are intelligent enough to have children.
I would never treat a gay man badly, even if he was to flirt with me once. But truthfully, if he was to flirt twice after being rejected, and try to tempt me from the rightful course, I would probably become a bit more furious at his degeneracy.
National-Trapism is the solution to this.
One man, one trap, and a female that is forced to breed with them, to ensure that our race continues. The female is executed at age 30, as it is seen as nothing more than a machine. Females are artificial wombs to ensure our genetic continuation. Females are not real people. They are machines meant to breed for us, and all other purposes are false.
Females exist for one reason: Breeding.
Traps are what are beautiful, and men are what are strong and noble and intelligent. Females are machines. Females are artificial wombs, and there is no need for moral consideration as to their existence. It is simply fine to discard them into the incinerator once it is no longer able to breed healthy children. There is no other use for it.
Traps play the role of gentle mother, men play the role of disciplined father.