Would not the other half be the women if half is men?
In reality, what you assert as a fact is indeed an opinion. The primary factors driving libido are physiological, followed by psychological end environmental factors. There is ample evidence that a large portion of “low libido” in the aggregate population is a result of the hormonal interference caused by oral contraception. Women have far more biological factors in their libido level than men. The largest and most obvious of these is the menstrual cycle which dramatically alters the levels of estrogen and testosterone over the course of the cycle.
That said, the author was not referring to “low libido” but really to differences in the levels between two people. The primary driver of that difference is age. Males hit their peak libido around 15–16 and start a long, slow decline for the rest of their lives. Women ramp up slowly until peaking around 35 before beginning their decline until menopause where it seems to become a coin-toss as to whether it will go up or down for a given woman. As a result since most couples are within 5–6 years of age difference, their levels will normally be quite different to each other — regardless of their sex.
And, yes, the same option already exists for women. The Sybian has been around for a long time and male dolls also exist. Indeed given the long experience in making aids for women bots for women are likely much more simple than for men.