Many homosexual men admit that they were seduced or introduced into same sex acts when quite young. Or they were out and out molested; but when even young boys are molested there is often some kind of sexual pleasure in it for them. I have read "advice" to young homosexuals that often anal sex is painful at first. They are advised to "keep trying" - to persevere, that eventually they'll find pleasure in it.
Your argument is weak. Why would anyone - same sex or opposite sex - "enjoy" bondage, sado-masochism, anonymous sex, group sex, bestiality, etc etc? These are all disgusting and painful sounding to normal people. Some heterosexual couples also practice anal sex, which disgusts and sounds painful to most people. And what about homo-weirdness like the cannibalism we are reading about? Where one homosexual offers to be eaten by another? Is that a biological imperative as well? Or is it just the logical extension of the philosophy of "anything goes"?
So why do they do these things? Because they are "born that way"? Or is it because their strong desire to enjoy pushes them to try acts that are farther and farther away from the normal and ordinary, since their lust burns very hot? And our sex-obsessed and porn-obsessed culture "celebrates" divsersity/perversity and offers opportunities for weird sex that previous generations never even thought of?
As long as it involves only living, consenting adult humans what does it matter to you? There are people who object to oral sex as sodomy.