I have come to believe that the driving sociological force behind changing morality is the scarcity/abundance dimension. As our invasive species outgrows its environmentally easy resources, some sort of rationing must take place. At the same time, homo faber figures out how to increase the resources through technology, making the stop-gap rationing scheme, which is always harsh for the losers, unnecessary and, therefore "wrong." The way we are wired, some of us must believe that the rationing was "always" wrong, but it wasn't, because there wasn't always an alternative consistent with the supply of resources to be shared.
One concern of men in an era of what seemed to them unending scarcity - history moved slowly once - is knowing that the children they risked life and limb for were their own. (Mama’s baby, papa's maybe.) Almost all of the restrictions on Muslim women can be seen as answers to the question "How do I make sure my wife is carrying my child?" Make sure she's a virgin at marriage by preventive measures, and keep her faithful by covering her up and accompanied by a male who can be trusted (maybe a eunuch if no brother is handy). Make men grow beards so women can't pretend to be men as they sneak out to liaisons. Even give them different words to use as a sort of shibboleth.
All this, I submit, is done in the name of genetic purity, driven by the scarcity of resources. Abundance brings moral laxness (see "Roaring Twenties") and scorn for what went before. I find Brutus's words, albeit out of context, apt:
But 'tis a common proof,
That lowliness is young ambition's ladder,
Whereto the climber-upward turns his face;
But when he once attains the upmost round.
He then unto the ladder turns his back,
Looks in the clouds, scorning the base degrees
By which he did ascend.
I believe moral absolutism is performative, but it is also a necessary tactic for effecting change. It is so much easier to convince people that something has always been wrong than that it has merely become wrong. What a piece of work is man!