"Homophobia is the irrational fear of failure to maintain sexually reproductive replacement in society."

No offense intended but this explanation reads like it was written by an alien who has never interacted with a human before.

People become homophobic because at formative years they imitate and internalize homophobia from role models.

Nobody is sitting around panicking about population levels.

Culture- such as the culture of homophobia- takes on a life of it's own. It does not represent beliefs or fear it just is.

Like a disease? Or a meme? An arbitrary custom?