Not that I'm a true anime fan myself... I can enjoy some anime work from time to time, and I have friends who are really into anime, even some even to the point that they know a bit of Japanese, and some of them have a really high IQ. Not that I agree with all their opinions, but agreeing and counting opinions are two different things.
By the way, I see the same hatred spread already towards Happy Tree Friends, Tik Tok, Fortnite, Justin Bieber and many other things. Now I do like HTF, but I don't like any of the other things I mentioned. A few jokes about them are fine (I will laugh about a few "Twilight" jokes too), but you cannot ban the franchises you don't like from the world and tastes differ. I hate Dutch smartlappen and German Schlagers, but nothing forces me to listen to them either.
In the end it's live and let live. Just because somebody loves Anime doesn't mean they don't know anything about non-anime related stuff. I guess it's human nature to hate each other, and if we do not have a reason to hate each other... then let's make one... Do I sound a bit cynical to you? I call it "realism" and that's the sad part of the story, I guess!