The overprivileged upper-class people are the ones spewing the BS, which is then lapped up by their followers and treated like it's religious dogma, where anyone who steps out of line is either ignored or outright shunned and attacked. That's what I mean when I call it a cult. They rope people in when they enter college and brainwash them with waffling nonsense about how things like the office air conditioning are actively sexist and serve "the patriarchy", all while campaigning for other likewise superfluous nonsense like "rape culture" or the #KillAllMen hashtag.
If I'm speaking to someone and they, with all sincerity, call themselves a feminist, my opinion of them will likely drop and my first thought will likely be something along the lines of "aww s***, here we go, he/she is going to say something retarded". The severity of this depends on how familiar I am with the person in question.
Though I must say I fail to see how the size or mainstream appeal of feminism makes it any less of a cult. I can name several other groups or organizations that I would call a cult, who also have rather large followings.
Though I don't know how any of this ties into rejecting groupthink. One would assume that, given how mainstream feminism has become (between individuals who hold their own private thoughts and ideas, to celebrities speaking about it on the news, to it having its own classes in schools and universities), the groupthink within the movement would be stronger and therefore more obvious to notice.
I see. So you're heavily stereotyping a very large group, then you say you reject groupthink. What I see is a sort of reverse groupthink, where everyone in a group is autocatically guilty of various intellectual sins.
As I see it, the #killallmen harpies are a very small minority of feminists in the grand scheme of things. Sure, there are idiots like that. Just like there are religious fanatics, bible-thumpers, ultra-conservatives, women-hater, racists of various forms, gun nuts, violent anarchists, violent communists, single-minded atheists, and all sorts of other entiled, close-minded, stupid people in any srot of socio-political movement you can think of and beyond. That's not part of feminism in particular, it's part of some humans just not being very good humans no matter what they are and what they think.
The vast majority of feminists I've met were reasonable, albeit often opinionated people. I've not always agreed with them, but they were not all shrill harpies, no more than the majority of conservatives were backwards, racist hicks or the majority of liberals were hypocritical jerkbags or whatnot. Treating such a varied political movement as a cult is just dismissive and doesn't seem like intellectual honesty to me.