Unfortunately I've yet to see any evidence to the contrary. You only need to see the amount of abuse people like Laurie Penny, Mary Beard, Sue Perkins, Dr Jack Monroe and Caroline CriadoPerez get when ever they commit the heinous crime of speaking to realise that it is true. You don't see if often, but even on this forum I've had replies to threads where it is an attack. I've been online long enough to know what happens. Sure it ain't pretty, but it's the price you pay for freedom of speech. Doesn't make it right tho.
The same could be said for their male counterparts though. You only have to look at the abuse given to Ronnie Pickering, the unfortunate fella that experienced a spot of road rage. The Internet has made mincemeat of him in a matter of days. Anyone, and I do mean anyone who puts themselves forward, even inadvertently on the web gets stick and I don't think gender really has much to do with it.
I can't speak for all you've mentioned, but I had the pleasure of debating with Laurie Penny before she started to write commercially. She is impossible to debate with as everything said was twisted around. Apparently I was misogynistic and juvenile for disagreeing with her on the most basic of points, and this continued throughout the debate with many others. Whilst I don't claim to know her in real life, she misrepresented some very fair-minded individuals simply because they were male. Not cricket at all and PennyRed as she was known then was quickly ostracised from the community because she couldn't hold a conversation without claiming that anyone who disagreed with her was an outright sexist and misogynist.
From what I can gather Jack Monroe was a victim of her own success, much in the way of Justin Beiber. She had a very marmite personality and viewpoint, and very quickly suffered the 'Attack of the Trolls'. Think about the way people talk about Beiber, how quick they are to abuse him (I do it myself) and compare it to what happened to Jack. Success, especially success from someone who could have been your next door neighbour breeds contempt and for some reason hatred.
In a previous life (not literally) I put myself up for scrutiny by expressing some heartfelt views, I shared the same platform as Laurie and I can tell you that the abuse I received, the personal threats and the character assassination (especially about my physical appearance) was vicious. I dared to express a view, a view that is held by many people but wasn't quite to the liking of several thousand people who took to the web to tear me apart. I took the abuse, I carried on writing and only stopped when I realised that the trolls were outweighing the genuine readers, so I decided not to continue. What tipped me over the edge? They chose not to just attack me, my appearance, my so-called status, but instead to target my children and my wife.
I'm afraid that when the old BBS network crumbled and the Internet arrived, the world became a much crueler place for those who have an opinion on the world. For every good the web has had on our society, for all the benefits of social media and the amazing advances in technology, what we've really done is unleash a dark side of what would normally be good people. A cruelty and a wickedness that only anonymity allows.
I hope I haven't offended with this, wasn't my intention... but what has happened to Rachel happens to millions everyday on the social network of YouTube. It isn't right, it isn't how the majority would act, but its people like me who wished and willed the Internet to be born, to expand and spread without realising the cradle of knowledge could turn into a monster just as easily.