There is a strong biological drive in human males to have sex. Men also don't have to deal with most of the potential aftereffects of having sex (STDs being a notable exception). So it's not surprising that many men might desire sex more. However, cultural conditioning plays a huge part in that. I don't think that the increased levels of testosterone play nearly as large of a part in things. If you had a culture where everyone (rather than just women) were systematically discouraged from having sex, I suspect that the numbers of men vs women who desired sex would be much closer to even, and the same with a culture where sex was freely encouraged in both sexes (especially if, say, you had reliable birth control).
As examples of just how pervasive the cultural conditioning against women having sex is, even in modern-day culture, consider the following:
- Despite the increased sex drive of men, women are largely blamed for having sex outside of marriage bonds. Specifically, if it's a married man and an unmarried woman, the "other woman" is considered a temptress. If it's an unmarried man and a married woman, the woman is licentious. I don't know how it works out when it's a married man and a married woman, not married to each other, but I suspect it's similar.
- Foreign women almost always have the stereotype of being "loose" and wild. The only time when this isn't true is when you have someone who's educated or experienced enough to know otherwise.
- Birth control mechanisms very specifically focus on methods women can use to keep themselves from becoming pregnant. Off the top of my head, the only one that's ever been designed for men to use is the condom.
- If a woman (or an adolescent girl) is raped, the impulse is to find some way to blame her for it. Such as, "she was dressed provocatively", "she was in the wrong part of town", or the all-time favorite "she was asking for it".
- Women with increased sex drives are considered to be whores or sluts, to the point where I suspect that women tend to suppress their sex drives to avoid the stigma of such a title.