Like a lot of places a smal subgroup of tumblr gets taken way out of context and way too far. Not every part of tumblr is SWJs and furries. That's actually a very small subculture. There are between 300-500 MILLION blogs on tumblr. It would be impossible to have every single one of those blogs to the run by men-hating left-wing nutjobs. I've seen some beautiful blogs, posts, and people.
They're not good either, but still.