This is neither true (I've personally known plenty of computer geeks of both sexes who aren't interested in hackathons), nor evidence of some sort of gender dif

This is neither true (I've personally known plenty of computer geeks of both sexes who aren't interested in hackathons), nor evidence of some sort of gender difference, since if the statement in the first place were true, you would have exactly one data point with which to correlate gender with being a genuine computer geek.