Both the Greeks and Romans were sexually free. They had some of the most advanced civilizations.
Nope ....
I see you haven't bothered to read.
Of the 86 cultures studied all of them went through a period of growth and decline then Collapse.
When they were progressing and growing building empires, developing art, culture and science they were a monogamous.
When the wealth from conquests trade routes and massive number of slaves flowed in, it led to one hell of an orgy the author calls it " with monotonous predictability".
That means it happens in every case , exactly the same way all 86 cultures give the same result.
Us Muslims avoid social issues when looking back into our history, they are more interested in battles , futux and raids or religious affairs.
It is embarrassing to accept but we had periods of sexual freedom in certain Islamic countries.
The places that reached the highest level of living where the most free and they all collapsed spectacularly.
During the Islamic golden age , parts of Afghanistan and eastern Persia were shockingly liberal for example alcohol was normal and nearly everyone drank. There was a bar/taverna in nearly every suburb if a big city or town, in little villages.
Premarital sex was more accepted
If you look up the poetry of Omar Khayyam it paints an interesting picture .
The dude was going from bar to bar picking up chicks and banging them like a drum after seducing them.
This was the 12th century.
Andalusia from 11 to 12 centuries was even more liberal than Balkh and eastern Persia even though they had the same level of development.
The Christians were deeply offended by the depravity of the andalusian taifa states.
There are stories of visitors from medieval Europe visiting Cordova and Seville and getting scandalized.
It's like taking an Afghan tribesman and throwing him in a Mediterranean swingers and nudist resort.
Lol.
Similar case in parts of Syria , but Iraq was always conservative but Baghdad was the exception large cities attract all sorts .
Oh and I forgot to mention hijab in many regions it was unheard of.