It is all trolls doing these things. If a troll notices someone is female, they posy sexist things to troll her and make her react for the "LULZ". If she was a man, they'd troll him by calling him gay or saying racist things to him for the "LULZ".
There is an Internet MEME that "There are no women on the Internet" that trolls use. I think it originated on 4Chan, IIRC. It has multiple meanings. One in that it claims women in real life use the fact that they are women to get free things and benefits, and that does not work over the Internet unless she shows some nudity in a picture. Another meaning is that women on the Internet use feminist tactics for attention on how sexist men are towards them and then act unlady-like (arsehole?) towards people and then cry 'foul' when they react and reply back. Not my definition, but ones the trolls use to justify their behavior and actions towards women.
I was once on Kuro5hin, it was another Slashdot clone, and was striven to be like Hacker News before there was a Hacker News. The trolls got on it and scared people off of it. Yes they targeted women using sexist remarks and harassment and bullying, even called some of the women as men pretending to be women. One by one the trolls picked on and bullied the users and ganged up on users by downrating their comments and stories until they quit. The editors refused to act and the owner thought it was funny that they did that to "people who deserved it" and so many users left Kuro5hin and it turned into a troll site. The trolls had scripts and web robots to control the comment ratings and story voting with sock puppet accounts and directed things on IRC. I was asked to join them one time and I refused, so I was made a target. Eventually I was no longer at that web site either. Yes I spoke out against the trolls and protested only to have my account deleted/anonymized so my account no longer worked. They put up a $5 paywall to keep the trolls away, but it seems the trolls don't mind paying for new accounts after they burn their old ones. I've never seen a technology or policy that effectively deals with trolls yet.