It is not a fact, is a theory that has been disproven multiple times. Archeologist had shown that children were raised by the whole group. You premise is false.

Also, if it were true, there won't be so many men who prefer experienced women (yes there are plenty of those), group sex, and many other sexual practices.

Female preferences show things like women cheating on older husbands who were rich (the providers their parents loved) with poor poets and musicians. We see many girls and women liking young DiCaprio playing poor artist in titanic over Arnold Swanzenneger or Rambo. Actualy pay attention to reality. Evolutionary theory might sound nice to you, but evidence on the contrary abound.

Sure, when women weren't allowed to work, they marry for survival. But that wasn't long enough for survival. And since most of the prehistoric diet was from gathering, not hunting, it could be said that maybe it was males who have a preference for provider women. XD

Male preferences for sexual exclusivity were because inheritance and cultural, not biological. By the way, some men adopt, so having biological children is not requisite for parenthood even for men. XD