Perhaps it's because it's not really a religious issue (just using that as an excuse).
Biologically people are repelled by homosexuality and attracted to adultery. That affects their state of mind, and they look for a reason for that and catch upon religious arguments.
What people get upset about is a cultural variable that is not consistent across times and places. Plenty of times and places, people have gotten at least as upset about adultery as about homosexuality.
Other times and places, not so much.
I get that it's the "in" thing now to hate on ancient texts to seem smart but ...
Quoting a writing from the ancient Jewish leader Moses is equivalent to studying the history of the peoples in those times and locations. Please, note that basically ALL nations used an enslavement "banking" system that basically boiled down to: You pay off your credit card by working for the creditor for a few years (or for however many years the owner thought was sufficient).
It has absolutely nothing to do with recent American slavery traditions embedded in deep racism and superiority complexes.
The only similarities are the translation of the word: slave.
The economics of ancient cultures was drastically different from how it has been for all post-1600s Bank of England cultures. :P
I don't think that anybody is distressed by the Code of Hammurabi, but that is because there are not people going around sincerely stating that they believe the Code of Hammurabi to be timeless and perfectly just, and Hammurabi himself to be someone to look to for ethical or moral guidance.
It is only when the historical context of ancient documents is purposely ignored or denied that those ancient documents become the targets of modern criticism.
"But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart." (Matthew 5:28)
"If a man commits adultery with another man’s wife—with the wife of his neighbor—both the adulterer and the adulteress are to be put to death." (Leviticus 20:10 NIV)
"As for your male and female slaves whom you may have: you may buy male and female slaves from among the nations that are around you." (Leviticus 25:44 ESV)
So, um, not a great book to pull random quotes from as a source.