@kiilas So I've long had a pet theory that basically no one is actually 100% straight or gay and almost everyone is some mixture of bi/pan/ace but most don't acknowledge it because of homophobia, biphobia, and binarism.
I further think that the vast majority of cis people are actually non-binary and just don't feel enough conscious dysphoria to break out of the oppressive institution of gender. The modern gender binary is such a recent phenomenon that it just doesn't make sense that so many people adhere to it unless most of that adherence is culturally ingrained.
@ALWETP @kiilas kind of the prevailing theory on women all being some percentage lesbian and seeing people refer to themselves as 80/20 or 60/40 etc instead of xyz-curious. Probably came up with by some het-boy unicorn-hunter or it would fit with what you describe. Why would female sexuality be any different than male sexuality after all.
I get the "motherhood is biological, fatherhood is social" argument, the biological imperatives aside, human sexual attractions are wide and diverse. Most males are socially homosexual until age 12. Boarding schools prisons and other segregation make quite an incubation of physical experimentation.
That being the case sexual norms as we understand them are more social than physio-biological. Granted the instinctual drive for procreation, as societies become more economically stable and sexuality becomes more recreational and separated from "love" and religious duty, more choices for sexual expression become available, and I see no reason for only women to identify with a percentage if that is how they see themselves. Even if there are straight men on the d/l who don't consider such behavior to give them a percentage :)
FWIW all variation from procreation, be it positional or what have you could actually be considered yet an additional "orientation". But I have been argued against such things before. :)