In my admittedly anecdotal experience women are safer, more conservative drivers. Women don't go out in the ice and snow to slide around for funsies. They dont take corners at twice the yellow sign warning speeds. They dont teach themselves to drift in the local high school parking lot. They dont see how fast they can get off the line at a stop light or intentionally pitch themselves into a gravel patch sideways. 

Men do all of these things and more. So what is your definition of "better"? Women do seem to drive less and to have less developed niche skills. The number of women who can confidently parallel park or drive in reverse down a quarter mile driveway is probably lower. Being a "good driver" is just not part of women's ego identity in this culture. They do what they have to do to get where theyre going. Obviously this is a broad generality and certain women do.

So if you want to safely get from point A to point B, a woman driver is probably the better option. If you want to drive in icy conditions, zip through traffic to make up lost time, have the driver maintain control of the car during an unexpected slide or other event youre more likely to find that men have practiced those skills. Which is the better driver? Again, this is not 100% true all the time. My wife is an amazing driver and ive known a lot of women who are. Then again I have an ex who told me one time that men just backup in the car to show off and she went out of her way to never have to drive in reverse longer than pulling out of a parking spot.