This post will be a bit fragmented. I chose to look at the specific texts in the Bible as the main part of the debate, because for me the Bible is authoritative. This post will quickly touch on some of the other regularly-repeated arguments on either side. Some are more about general themes that are claimed to be in the Bible, and some are more driven by science.
The Natural Argument
This is the most frequent one that I hear from the Side A part of the debate. Sexual orientation is natural, so how can you say that it is wrong if God made it that way? To me this is missing the point. At least within Christian theology, we acknowledge that humans are both image-bearers of God (good) and broken (bad). This argument tends to rely on the fact that if it’s natural then it must be good, which could be scarily applied to other things like anger, greed, drug addictions, etc. No, the Side A proponents don’t make those kind of extensions themselves, and that is my point: they seem to make a bit of a special case of sexual orientation saying that, well obviously it comes from the good nature of humanity and not the bad.