Forums can also be used for enclosed echo chambers.. just saying.
Except forum posters here do not get to control who gets to say what. Dissenting opinions are given equal footing to make their case to the common reader. Posters face each other and while they can chose to ignore people, they can not prevent others from being heard. It is an equal ground where you must face your detractors - you can't run from them.
But that is why these people have abandoned forums and flocked to twitter. Even though twitter was intended to be a fully public open medium - over time they have added tools to combat harassment. Tools, this group of Disney fans use to not combat harassment but instead shape the world as they want it to be seen.
They like twitter because they can be seen as public, and broadcast their views to everyone, yet still selectively decide what reality looks like. They use the tools designed to combat harassment, but instead use them to shape how they want their tweets to be seen and who they have to face.
On twitter, they mute to ensure dissent is not seen by them or in their twitter responses. They use mute or block as a way of trying to force the world to be as they want it to be. They get to selectively read and control the presentation. The result is a self-feeding cycle of only positive feedback and a view that everyone is as you do. It's a false world.
They strengthen their beliefs by surrounding themselves with like minded folks and collectively shun those that would oppose them. You might say some do the same here.. but it's not the same because the forum is neutral turf and the poster can not create the sole reality they want. Their threads and posts can not exist in isolation. Posts are taken in context along with the content provided by other members - you can't isolate yourself but instead must be able to face both positive and negative feedback. You'll find a common behavior in the Disney twittersphere which is retreating to twitter to talk about someone rather than facing that someone. They'll even do it in twitter by talking about other users without tagging them. It's that exact catty, yet unable to face people that helps fuel their juvenile behavior.
Most of the Disney twittersphere are no longer active on forums. I'd speculate it is because they can't control the content like they can in their twitter bubble.
Case in point.. look at these tweets
https://twitter.com/BrianPMiles/status/473586669967265792
@BrianPMiles
On social media you control who you interact with. You are given many tools to avoid interacting with people who aren’t your cup of tea.
https://twitter.com/Illusion0fLife/status/473692393774907393
@Illusion0fLife
Today has reinforced my belief that I'm following all the right people. You guys are awesome.