Basically she's a woman who started a series investigating sexism in games, she's not 100% on point all the time but hey nobody's perfect. The issue the internet has with her is that "MAN STUPID GIRL IS TELLIN ME SOMETHIN'S WRONG WITH MY GAMES" as if that means they're not allowed to enjoy them anymore and they're not able to recognize that maybe there is a problem there. Then again, critical thinking's never been a strong point for people online has it?
Basically, since a woman wanted to talk about something that she felt was insulting to her and other women a bunch of manbabies decided to start attacking her.
It's quite literally a harmless series of videos that draws the vitriol of hundreds of people. The internet is a very silly place full of very silly men.