Nobody is omniscient. Nobody truly knows what someone else is thinking. Sometimes we don't even know ourselves. So when theories are established, they are never perfect. The so-called "majority" only appeals to the notion of conformity and is often only supported due to believing in half-truths. 

I.e. 

Proposal: We must do whatever it takes to prevent war.

People support (sometimes blindly) because they believe that war is bad.

War can only be waged if there are two sides. Therefore, if both sides are destroyed then there is no war. The public does not see this fine print - they only see anti-war activism, unbeknownst to the cost. 

The cost = kill everyone then nobody else will be left to be killed, hence no war. 

But back to criticism...

Since we cannot fully apprehend what everyone thinks, there is (possibly) no universal theory that is valid. We all support our own worldview that we see within it, but never the full story. We see what we (subconsciously) want to see. We (subconsciously) fool ourselves into believing we are doing what is "right". 

But we never know for certain... and we never can. (But isn't that what makes life worth living? The challenge?

Because we never know for certain, we can only critique. We know what feels wrong, but aren't certain what feels right. Therefore, we can only change.

And change isn't always for the better.

The current status quo doesn't work. It never will, but it can come close to perfection. 

There should not be any "well can you do any better?"; we should accept destructive criticism because spite and rage are inspirational factors. 

There are no "bad" emotions. There should be no mollycoddling, no bubblewrapping, no sugarcoating. Take things at face value.

Only then can we open our eyes and see, we have always been wrong, we always will be wrong, but we should never stop moving forward. Stagnation is death.

So the next time somebody says "you're wrong", accept it and embrace it. Thank them without sarcasm and don't expect them to give you pointers in the right direction. If they do, that's great - try it to see if it's better, although be prepared for failure -, if they don't, then it's not a problem. We are animals of instinct and don't always have reason. And reason is not always right. Trust the 6th sense. 

All in all, if someone says you suck without reason, that's because you do. You are not perfect and you are not better. You may have comparative advantages but you suck like everyone else. The point it to understand you suck and try something new. New may cause you to suck even more but as Edison once said: 

"I have not failed. I've just found 10,000 ways that won't work."

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Edit: 25th Mar 2021

Hypocrisy might seem to be a bad character trait, however, some of the best connoisseurs are the worst chefs. Just because one might suck at art does not prevent them from criticizing the Mona Lisa. We should accept criticism from everyone because sometimes the best advice comes from people who are complete amateurs.

Don't go around spraying "whataboutisms" – it's disgusting.

You have the right.

Believe it!

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Edit: 3rd May 2021

Also... Coaches don't play.