You say that one "fundamental law" that does "not change" is the topic of this thread. And yet, have you actually looked at the list of religious organizations that disagree?
LGBT-affirming religious groups - Wikipedia
Granted, you will assume that they are all wrong (in their quite literal billions), but one cannot help but again see this is as a dismal failure of an all-powerful deity. If this is so important to that deity -- and if that deity has the power to make it know to all mankind -- why is it not? One of the premises has simply got to be wrong.
(Of course, my view is that the premise that there even is such a deity is wrong, but even if I'm wrong, then at least we must admit that either the premise that He deems it wrong, or that He wants people to know it, or that He is omnipotent and capable of ensuring it is know, simply must be wrong.)
That's an exhaustive list. I'm surprised actually at the number.