If this were the 1950s, I would just say two words, 'personal responsibility', and everyone would nod in agreeance as it was well-understood at the time. But in the age of the internet that's not really feasible, because you pretty much have to write a paragraph to have a chance at helping people understand a concept that was once taken for granted.
While I cannot seem to locate it, there was an article I read from my Pocket the other day describing the addictive and dehumanising effects social media and online interaction in general has on human psychology and sociology.
Simply put, people are worse at interacting with others online a lot of the time. The problems in recognising this are several:
- Much of the poorer reactions to things are quite inconsistent and translucent, and therefore largely go unnoticed and are hard to identify;
- Explaining the problems with how someone is acting is incredibly difficult, because it all makes sense in their head and there is no empathetic bridge to say otherwise;
- The echo chambers, as you call them, are a product of this disconnect, and they solidify said problems and set them into stone through collective confirmation biases.
I think the primary cause for this is that online, we are not talking to anybody. All we are doing is writing notes to each other, or sometimes papers (like here), and a lot of the human interaction is completely lost in that process and there is no feasible way to replace it in a lot of circumstances. Because this is not a conversation, truly, our minds must simulate it as if it were one, so we can make sense of our situation and do our best to be sensible and rational. This often ends in disaster, as our minds must do the best they can to 'make up' whatever human interaction is absent, and because we all think differently we often tend to make up different situations surrounding a conversation and problems arise from that.
In light of this insanity, many people feel a very natural need to cling to perceived similarities and like-mindedness, because on the internet there is no other way to actually bridge a feeling of common ground than to actually have the common ground in plain sight, often as an opinion on some subject or another. Because we don't feel inherently warm and connected to a scrap of text, we must find a way to rationally construe that in our own minds, and that's really difficult to do when all you have is said text. This is why opinions have become so sacred, and disagreements so nuclear - there is nothing else to really go on.
When someone writes you a message, in their minds they're being honest and reasonable in the vast majority of cases, because that's how they naturally are. But after a point it becomes difficult to register one's own disinhibition, and even the best of us will start to write and say things that feel normal but register as unquestionable hallmarks of a complete asshole to everyone else, which would be made painfully clear if their text was put into a face-to-face spoken word and shown to people as if it were a real, two-way conversation.
Still, I don't think that the often-cited Online Disinhibition Effect is a final explanation for things, not just because it's psychology (one of the murkiest fields of science we know), but because things are still so new and so incredibly volatile that humans need to think and talk about it more together. I certainly don't see the ODE as any kind of summary for why trolls exist online, or why people disagree so passionately over things they'd easily walk away from at home or in class. But it's a definite start on things, and my penchant for psychology makes me want to learn even more.