Is Demisexuality the Norm?

I don't think it's that rare to require a strong emotional bond to be sexually interested in someone… it's just that the kind of people that don't require this are a lot more extraverted and therefore easily become the focal point of our society, especially as it becomes of an ever larger scale: eventually they become popular and we make them our role models, but they're really just a very particular kind of personality that makes up just a fraction of the human population. In hunter-gatherer and agrarian societies, it didn't evolutionarily pay off to be promiscuous at all (except when raiding other tribes to rape their women) because within the tribe there's obviously a one-on-one ratio of men and women and all the women would be taken quite quickly, as everyone knew each other from childhood, so that they had all the time they could possibly have to deliberate who they'd marry.
Without violence, there was no way to upset this balance, so cheating would mostly just endanger the relationship, and in a tribe, it would be almost impossible for cheating to not be found out. It's only in urban settings that cheating became an evolutionarily advantageous strategy in some cases, and until very recently, most people didn't live in cities. With the unfortunate exceptions of war and crime, we are genetically a monogamous species — we just live very long lives, and no other monogamous animal could stay together for as long as human couples do. It's hard for me to believe otherwise than that the majority of the population, including men, is demisexual at heart, and our preconceptions that it's otherwise merely arise from the fact that the few exceptions are very salient in social circles, because they're so extraverted.
But, on the other hand, I'm biased myself because I am demisexual and literally can't imagine being attracted to someone with whom I have no intimate bond. The truth is probably somewhere in between both biases. So it's with all humility that I mean to present these speculations.