It seems that nowadays two kinds of communities reign over the realm of the internet:
1. Laydback communities
2. Thick-skinned communities

Laydback communities are places where you can lower your guard, 'problematic' opinions are not allowed, hence they are suppresed by following the 'don't ask, don't tell' rule, or by removing any and all persons whom follow a problematic opinion from the community.
These spaces may devolve into a circlejerk.

Thick-skinned communities are places where it's every man for himself. There is no concept of 'problematic' opinion in these spaces and you are expected to stand by your opinions.
These spaces may devolve into an extremist (any kind of extremism) circlejerk.

It is common for both communities to hate each-other's guts for their own ideological reasons.

I do not believe every community manager out there is amateurish or immature, so there must be some underlying issue that is causing this sort of behavior.

Let's explore a few personal hypotesis, I'll add a section at the end detailing what you can do to fight these issues:

Perceived problems and personal hypotesis:

Observation:
Instantaneous interactions pave the way for kneejerk reactionism and raw emotions rather than critical thinking.

Hypotesis:

By encouraging users to write small amounts of texts and indulge in chain-consumption of media without any critical thoughs, we have created a herd of passive reactionaries.

The brain needs time to process things, it's like a queue in 'the sims' game, there's only so much information your brain can process at a time.

If you read four mangas, half a book, a comic, five reddit posts, eight hours of youtube and who knows how many thousands of short videos in a single day, your brain will obviously be unable to process this amount of information whilst you sleep.

You're experiencing symptoms similar to those of ADHD because your brain is panicking; The queue is overdue by a month and every day a week worth of queue is loaded on top of it.

It is no wonder that you cannot concentrate enough to read five lines of text, your brain is working it's hardest to make sense of all the things in the queue.

Demolishing your attention span and having a brain full of stuff to process greatly diminishes your desire and capability to take your time to consider something, consider your feelings, think critically about it and finally write down a proper response.

We have some in-grained opinions that are basically knee-jerk reactions to certain things, these opinions might masquerade themselves as well-though answers, but they do not benefit the individual spreading them;
To think about something and post a proper answer is an exercise on critical thinking, it helps you develop your critical thinking skills, sometimes it forces you to research a topic and learn new stuff, and in general is a positive experience for both parties.

Knee-jerk reactions, on the other hand are just automatic responses to display one's opinion on a matter.
They do not benefit the individual outside of maybe facilitating social bonds, but they do benefit themselves;
Knee-jerk reactions can spread like mind viruses. Have you ever found yourself mindlessly writing 'lol' without giving it much of a though?

I challenge you to spend a whole day without mindlessly typing a 'lol', 'xd', 'based', 'cringe'. You will soon realize that breaking this habit is a bit harder than you expect.

'lol' is just a harmless no-emotion but some reactions are far more harmful. Some people will write full sentences, maybe even four lines of text to expose a point that's just a mindless knee-jerk reaction. An opinion that has not been researched, nor considered, it has just been accepted as truth by the tired mind.

This herd is passive, in the sense that they do not think. They only consume, they consume someone else's opinions and ideas and adopt these as their own knee-jerk reactions.
Then, they spread said reactions around the world, never taking the time to think about it at a deeper level, outside whatever is discussed at their ecochambers.
And I do not say this as an 'outsider', anyone can become part of a 'herd', all it takes is to stop thinking for a moment. I am not excempt of this.

Observation:
People are treating opposing opinions as threats to their safety.

Hypotesis:
During the past years a them-vs-us mentality has been cultivated globaly; it might have been a byproduct of human nature, capitalism, power struggles or something else, but I don't think we'll ever know what started it.

The issue comes from the constant buzz of a fight that echoes through every nook and crany of the modern world, be it Men VS Women, Left VS Right, Chrisitanism VS Atheism, this constant conflict is degrading the quality of human interactions.

It is worth mentioning that opportunists have taken this as a chance to further their personal and or ideological agendas, claiming that the root of the issue can be traced back to [X].
(X changes depending on the ideology, you can replace it by: "Capitalism", "The jews", "The system", "The left", "The right", "Corporations", etc...)

The influence of these oportunists has only helped to further degrade social interactions, reinforcing the Them vs US mentality.
Worse of all, opportunists create enclosed spaces with an alarmingly low diet of varied opinions. These enclosed spaces are by far the most virulently noxious places for a person; People who think the same way spend alarming amounts of time and energy reinforcing one another's prejudices instead of solving problems.

How to fight it:

• Remember that the person you are dealing with was once an inoccent child.
  
  No one is born 'evil', every single person on this planet has reasons behind why they do what they do, and why they believe in what they believe.
  
  Even the most greedy, hateful asshole was once a little child, something pushed them to become the way they present themselves, you must understand this and be patient, tolerant, talk to the person and try to understand why they are acting the way they are.
  
  Most people, except for trolls, get heated over arguments or discussions because they believe they are trying to help others. Keep this in mind.



• Think, use your head, use critical thinking.
  
  If you like an idea on paper, spend some time thinking about said idea critically. Here's a critical thinking cheatsheet to help you.
  
  It is only by understanding both the good and the bad about the idea that you can figure out if the idea is worth supporting, if someone is attempting to manipulate you for their own gain, or if the idea can be improved upon.
  
  You don't need to do this about every single idea and concept thrown your way, you'd be overwhelmed.
  
  It is ok to have no opinion on certain matters if they are not relevant in your life.



• De-escalate and respect the other person
  
  If an argument is getting heated, don't use this to your 'advantage', show the other person you are a human being and not some caricature, this goes both ways.
  
  If a discussion or argument is getting heated and emotional, it's alright to point out the need for a break to gather some thoughs.
  
  Respect the person you are talking with, you're both humans and if you got angry at something someone else posted, you too would be happy if they treated you with respect instead of making fun of you.



• Accept that stuff is personal and fluid
  
  I know it is hard to admit someone else is right about something, but this happens, and it happens a lot.
  It is important to maintain some humility and shallow one's pride. If someone pointed out your argument, logic or worldview is wrong and provides you proof of this, do not take this as an insult, but as an opportunity to strenghten your own ideas.
  Acknowledge the valid points the other person provides, and talk about it, try to find out if there is a better way to do things; Improving your own stuff is in your best interests.

Remember that before incorporating change, it is important to apply some serious critical thinking into it.

Identify what is relevant.
Watch the news for a while and you will now know that someone's car exploded, that someone shot-up a church and that someone got santa adicted to crack.

Great, is ANY of this information relevant at all for you?

• 1 person's car exploded about a thousand kilometers away from you whilst a billion people drove their cars normally.
• 1 person shot-up a church in another country because he was insane.
• Santa does not even exist, this is obviously made up.

Unless you live in a terrible place, chances are if you walk outside the house, no one's car is exploding, no one is shooting a church and santa is still not real.
Was any of that information they have served you useful at all for you?

The internet is full of useless information like this, this kind of 'dud' information is irrelevant for most people, it's only purpose is to benefit the person that is serving you said information.

Make sure you identify and discard irrelevant information, if you pay ears to every single asshole out there screaming 'the end of the world is coming', you'll end up a nervous wreck with a revolver with 1 bullet on your belt, just in case.

--But alien ar--But the war ove--But the nuclear--But-

Look, honey, if society or the world is going to shit it's pants, it's going to do it regardless of how scared or angry you are.

When the bullets are flying, the people are fighting each-other and assholes with tiny hats are claiming to be the messiah, it is then, more than any other time than the world needs calm, level-headed individuals to think things through before we conglomerate into a big dumb mass and put the next big mistake in charge of humanity's well-being.

Now, this whole section might be seen biased towards the second category of community, but it is that way because diversity of opinion is never a bad thing for a community, as long as all of the members know how to handle other opinions.
Having laydback communities that scrub bad apples is also not a bad thing, as long as the community masters know whom to ban and why:

• Trolls
• People that willingly refuse to follow the principles laid on this book, to the point it starts hurting the harmony and morale of the community.
• Illegal stuff/Breaking rules/Inhumane acts, etc

I think this is a good moment to note that being understanding and tolerant does not equal being a little cloud that anyone can walk through.
As an individual one should try to be kind and tolerant, but that does not mean you need to be a teacher, a babysitter, a shoulder to cry on or any of that.
You are only responsible for your own happiness and your own experience, if you don't feel like interacting with someone, just don't.

Being tolerant, kind and respectful does not equal having a responsibility towards other people.