I think it may have more to do with the latter. A quick Google Scholar query of "why is computer programming dominated by males" provides some interesting resul

I think it may have more to do with the latter. A quick Google Scholar query of "why is computer programming dominated by males" provides some interesting results, including an abstract with the key finding that "men had more confidence in using computers than did women even when statistically controlling quantitative ability. In fact, female CS majors had less computer confidence than did male non-majors." (Beyer et al., 2003)