Not sure about why fewer women identify as “none”, because it seems to me religion is generally unkind to women (with the exception of some more liberal denominations). I couldn’t identify with a religion that blamed my gender by proxy for all human suffering and expects me to be silent and submissive.
I do find it disconcerting that most public atheists are male. I can’t come up with the name of a famous female atheist at the top of my head. A lot of people are probably under the impression that all atheists are angry white guys!
