It's just tiresome. I, like a lot of people my age, cultivated my feminist ideals through tumblr. In that way it's great for getting young people to say "I don't like how I'm being treated and I want to challenge it."
Most people on there are, or were, 13-25 give or take. And what do young people really like? Cliques and categories. And that's a two fold issue. The cliques, the most popular blogs were setting the bar of acceptability. What's oppression, what's activism, what's not. And actually there, you do see the anti-trans man rhetoric that Mumsnet thinks is mythological. There you get all kinds of flexible thinking. If my male partner and I both transitioned, I, in my newly obtained trans man identity would have ALWAYS had more "male privilege" than my (formerly) male partner. Always.
The other point is that young people like categories. When I was 14 it was goth, emo, whatever. Now you go on tumblr, and there's a whole tumblr dedicated to listing gender identities. Complete with latin names. So now aspects of your personality, no matter how ambient, are your gender.
So really thats the atmosphere educating a lot of young people. I don't know a lot of people my age still on tumblr, but while the people and the attitudes have grown up, the sentiments remain the same. It's a semi-utopian one: we don't want anyone to be sad or hurt or oppressed. That's noble. But in order to create this utopia NOTHING gets questioned or challenged. Trans women, especially ones marginalised in some other way are the most unquestionable. They can never be wrong. And really it's a lot easier to make feminists and lesbians an easier target than MRAs, Nazis, fundamentalists, government or dare I say the general populace. All of whom have a much more ferocious view of trans women, and contribute much more to trans suffering. But aren't lesbians and feminists so much more accessible and easier to break down than all that?
It's only when you start reading outside the echo chamber including works by academic feminists (rather than EF articles and someones blog) that you begin to question it. I began by lamenting that so much of the anti-porn literature was so anti-trans. Then I realised I couldn't deny or refute the gender criticisms either.
And I don't want to be a downer on or patronise young people. It's a tough atmosphere where you don't want to offend anyone, you want to be good, accommodating and this lets you take a principled stand in a very easy way. But it's misguided, I think.