The procreation argument is easily refuted (as it is in this article) by pointing out “what about couples who are unable to conceive?” Never mind that it’s a statistical aberration, a system not working the way it’s supposed to, just “what about...?”
As to giving “a pass to the adulterers”...maybe. I’m not one of them. I’m not going to scream for their beheading, but I wouldn’t scream for the beheading of a homosexual either. I would still tell them that their behavior is wrong and they need to change their ways and it has no place in a civilized society. Self-control is still a thing. There’s no debating the merits of it or twisting the Bible. It’s very plain.
But we are too permissive. Maybe we don’t need to make people wear the scarlett letter, especially if we let one partner off the hook. We are too far down the road of “not judging,” and a long way from the standard that Jesus laid down. Small things. Why don’t we require modesty while dressing for church, or for that matter, even for school? Because the larger society is calling our children and we are afraid we might lose them. Never mind that there is a good reason for not calling attention to our physical assets. We mock the Muslims for their dress, but they have a point. Why advertise if you are not selling?
Couples who are unable to conceive are still supposed to have sex which is in the procreative form and to avoid perversions thereof, e.g. oral/anal. Just as Biblical Abraham and Sarah, though past the age of childbearing, still made their sexual union in the natural manner as a “sign” of their openness to life.