First of all there is far more than Michelangelo and JUST the Sistine Chapel. Point being: the Catholic Church’s artscape leaves room for sensuality, mystery, and yes even the contradictions and spiritual struggles of its adherents (like Michelangelo and others.)
By taking on the flesh, Christ redeemed Creation.
Perhaps Michelangelo’s homosexual desires and struggles were redeemed by God and put in the service of His Glory. Beauty from the pain.
And Michelangelo’s works, especially pertaining to the Crucifixion - definitely capture pain masterfully.
I did a report on Michelangelo three years ago for my Faith and Art group. Wow, what a splendidly gifted man! And he knew he owed it all to God.
I would argue that, whatever his internal struggles --- and they were lifelong and felt full-force --- there's credible evidence that he never engaged in homosexual relations.
Unlike almost all prestigious sculptors of his time and place, he did not live with, and barely tolerated, apprentices, though many ambitious parents urged him to accept their sons in his workshop. According to one account, some would more-than-broadly hint that such-and-such a young man was very attractive and would be good in bed, and he literally chased them out the door with physical force.
He was ascetical and solitary in his personal life, which also made him most unusual for the elite artists of his day. His contemporary and biographer Condivi called him a man who "withdrew himself from the company of men," describing his "monk-like chastity".
My own take on it is that he had a romantic affection for men, which he sublimated into his powerful art.
His 300+ sonnets and madrigals unquestionably express a passionate attraction to the male form and the anima maschile, and also a passionate devotion to God to Whom he dedicated his solitude and his genius.