We all know the FACT (not open for debate) that the anonymity (or close to anonymity) of the Internet causes people to be less polite, more outspoken, more misbehaved in general, more prone to harsh arguments/fights, and in general more uncharitable online compared to real life.
So what to do about it?
First of all, let's get this out of the way: The Internet or online discourse in particular has SOMETHING to offer, something very good, which is worth all the bad. And everyone here agrees with me on this point (if they are honest!), or they would have cancelled their internet, uninstalled their browser(s), etc. by now. Because no one is forcing them to use the Internet, or visit sites where other human beings communicate.
So, again I ask, what to do about it -- and whose fault is it?
You really can only blame human nature. Humans WILL be less "good" when they feel anonymous. This was discovered hundreds of years before the computer was invented. Ever heard of a "masquerade"? People would go to a dance/social event where everyone wore masks -- it helped lower everyone's inhibitions. They could sin more boldly. It was "fun" for that reason. Yes, I'm sure plenty of sins were committed, and one might even say a masquerade ball was an occasion of sin.
But the point is that anonymity = less inhibition.
So do we propose changing human nature? No, God designed us a certain way, and Original Sin did its number on us afterward -- and nothing is going to change the net result. There is no transforming the basic fallen nature of Mankind, as it has existed ever since the Fall.
So is there nothing we can do?
YES, THERE IS. You have to remove some of the anonymity. If you have a screen name that says nothing about you, and you have shared NOTHING about yourself as a person, as a human being, as a child of God with feelings, hopes, dreams, and "when pricked, you bleed", then HOW can you blame ANYONE online for treating you like a CONCEPT to be opposed, attacked, etc.? You ARE just a concept, if you aren't humanized.
And yes, IDEALLY we'd all be saints, completely going against any motions of our lower nature that weren't in accord with reason and God's law. But that can't be realistically expected in this life. There will always be PLENTY of sins, bad habits, and imperfections found in any group of hundreds of people.
So the only REAL solution is to not require people to swim upstream so much. Make it EASIER, more in line with human nature, for people to be good.Because otherwise, you're just a name that's on "the other side" -- Sedevacantism, globe earth, evolution, or whatever topic is being discussed. All gloves will be taken off. No quarter, niceties like "politeness", or treating a fellow human being with charity will be given -- because error is evil and has no rights -- and all you are is a screen name espousing or even representing/embodying some error. You are a mere concept; you aren't a plumber and father of 6 living in North Dakota or a thirtysomething housewife with an autistic child living in Wisconsin. (yes, those super-specific details were completely made up. These hypothetical persons were pulled completely out of my... ...brain.)
An online website with a bunch of anonymous screen names is like a "Debate" video game, where words are analyzed to see who wins each argument. Imagine if they made an AI chat bot that argued with you in some "debating" video game, and you got points for winning arguments. Would you be nice, polite, or charitable with the AI (the computer character)? Of course not. That's how many people act online.
So if you haven't taken any steps to humanize yourself -- share a bit about yourself as a human being -- you really deserve to experience what human nature DOES with that anonymity. Seriously, who are you going to blame? If you startle a human, do you blame him for being startled? If you cut a human, do you blame him for bleeding?
Psychology is real. The human mind acts in a certain way.
There are certain facts about the way the human mind operates that can't be changed. You can have human psychology work FOR you, or you can have it work AGAINST you. The choice is yours.
And I'm not saying you have to doxx yourself, but don't be too high on your horse either. You aren't as important as you think you are

For the most part, no one gives you a thought one way or another. So don't be afraid to reveal your general geographic location, your sex (we currently have what, 4 billion men and 4 billion women on the earth?), your general career, your marital status, etc.
Even if we figured out you're Joe Blow sitting in the SSPX chapel pews every Sunday in Florida -- WHO CARES? You're not that important. No offense. Some Trads need to be a lot less paranoid and self-important.
You don't have to give out any information you're not comfortable sharing. But if the beginning AND ending of what you're comfortable sharing is a screen name of "Anonymous001" -- no other personal information -- then I'm sorry, but with all due respect, there's probably something wrong with YOU. You are paranoid, schizo, and/or have various issues. And you can't blame others for treating you like a concept, a computer opponent, or a piece of software.
(And if you do have some good reason for such perfect anonymity, so as to never mention even vague facts about yourself as a human being -- then at LEAST don't be a hypocrite, and UNDERSTAND why people are treating you like a concept or software. Be patient about it. Because to them, at least psychologically, that's what you are.)
Human beings weren't created to deal with "avatars", or screen names representing human beings. Our minds were created and designed to deal with human beings in person, or at least long-distance letters, phone calls, etc. And all those things were highly personal. You always knew you were reading/listening to a human being.