Why the vast majority of 4chan users or most internet forums for that matter are males?
I will start with my low IQ take. I think it is because woman have very little incentive in society to do anything other than stay pretty to attract possible mates. Nature and society has wired them in a way they dont need to prove much self worth, men will be always there for them (trying to fuck them), whereas men became isolated and society outcasts thus forming this communities.