As a RWBY fan, from the thumbnail I expected this to be some long ass rant about how RWBY sucks, it's fans are pedos or woman-hating weebs. Then I saw that it was Gray from RT who was the writer. Why is it that I as a RWBY fan am almost always on the defensive when it comes to the show?

Because it's one of those shows that'll probably never have something in a similar fashion to it, and we want people to see it as a good show without others pointing out the problems it has. Because if and when RWBY stops, we want others to see it as something special that works, so other can also try to do it. At least, that's how I see it.