Neither of those explain this:
Average score for male neurotypicals: 81.4
Average score for female neurotypicals: 84.3
That's a small difference, but considering the numbers involved (sample size of more than 56,000 neurotypicals total) it probably does carry over across the general population.
Unsuspected, undiagnosed female autism would have to be this socially pervasive epidemic for a few spergy girls to skew the results that far, especially given that we could expect a lot of spergy dudes to be oblivious and undiagnosed.