Remember, we're talking about the outliers here, the tail end of the distribution founding billion dollar companies. Here's a thought experiment. Take two normally distributed populations with the same mean. But one of them has a slightly higher standard deviation. How much higher does the standard deviation need to be before the combined population tails (at both ends) are dominated by the population with the higher standard deviation?

You see men don't even necessarily need to have inherent (biological or social) advantages over women... they may just be more erratic and have a higher spread, and bam, they're producing both more serial killers and more geniuses. You can speculate as to why they might have a higher st. dev, but I think it is an interesting line of thought.