According to the recent investigation into homosexuality, the consensus is those who describe themselves as homophobic almost always turn out to be gay and closeted. For wahtever reason, rather than accept being gay and having a gay life, these people deny themselves and spend rather a lot of time making negative comments about gays.
More interesting though is the related question this research raises, namely, are the opposing sides of things usually in fact of or belonging to what they vocalize their opposition to?
https://www.psychologytoday.com/blog/the-big-questions/201106/homophobic-men-most-aroused-gay-male-porn
"When viewing lesbian sex and straight sex, both the homophobic and the non-homophobic men showed increased penis circumference. For gay male sex, however, only the homophobic men showed heightened penis arousal.
Heterosexual men with the most anti-gay attitudes, when asked, reported not being sexually aroused by gay male sex videos. But, their penises reported otherwise.
Homophobic men were the most sexually aroused by gay male sex acts."
Can google 'homophobes most arroused by gay porn' for the other umpteen thousand results if you like.