t's an immature worldview in which 'the opposition' is always completely lacking any kind of nuance. Everyone disagreeing on the new Ghostbusters movie being a godsend for women all around the globe (for instance) must be a puppy strangling neonazi trump-voting moustache twirling unrepentent asshole without even a shred of good in them. Period.
Amusingly enough, it's exactly the same when it's the other way around. They see absolutely no nuance with minorities either and they pull generalizations from their ass that would make any racist blush. And their own side is also the perfect embodiment of everything that's good and just.
It's why they are so fond of "no true scotsman" the moment an SJWanker fucks up and they have to ostracise them. Suddenly, they have never been true SJWs, all that jazz.