Have you ever been in an average disagreement/civil argument with someone? Of course you have. We all have. But do you ever have it happen where you are sitting there, respectfully arguing your point, and the other person starts yelling at you, and instead of being able to listen to what they're saying or yelling back in kind, you just want to either laugh in their face or get up and walk away?
That's how my mind operates. I can't even tell you how many arguments I've been in through my few decades of life, but I can tell you exactly how many times I felt the need to just get up and walk away because it was no longer about hearing one another out, but instead devolved into the other person trying to assert dominance by seeing just how much louder than me they could get.
I cannot listen to people anymore when they resort to yelling. I'm a very soft-spoken person myself, and I can't actually remember the last time I yelled at someone with any sincerity.
I know I have yelled. I know I'm not some anomaly of a human being that's just so above standard human emotion. But I can say with sincerity that I learned a long, long time ago that yelling never gets your point across simply because it makes you louder; it just makes you sound like a primitive asshole.
You know who yells when they're trying to get their way? Toddlers. Children. Oh, and monkeys. They'll hoot and holler because that's the only way they know how to make their voice heard.
Civilized adults shouldn't feel the need to yell at someone to be heard. For me, when someone resorts to yelling at me, I don't hear what they're saying anymore; I only hear the subtext of them thinking that I'm not astute enough to understand their words unless they're shouted into my ears. I hear the insult of a person thinking I'm not smart enough to understand what they're saying. Their point no longer matters at that juncture because they completely threw the idea of respect for me out of the window and into oncoming traffic.
And I, for one, don't tolerate that kind of insult. You can think I'm stupid. You can think I don't get what you're saying. But if you are in a position to think what you're saying is so much more important/correct/meaningful than what I'm saying to the point that you feel you need to yell, you've knocked yourself down a few rungs on the intelligence ladder by not being able to formulate your thoughts well enough to make your point make more sense through your wording rather than loud noises.
And you need to learn that it's okay to agree to disagree. If you're in a disagreement with someone, and you've both presented your cases fully and one or the other of you still isn't seeing the issue through the eyes of the other, you don't have to yell about it. That's childish. Grow up and disagree respectfully like most adults do.
Oh, and just as a side/final note that's related but not necessarily exactly my point here: to people--fully grown adults--who slam their computers/keyboards/phones/other technological devices around in anger when they aren't operating the way you'd like them to, I want to repeat something my third grade teacher once said to a classmate who acted out in such a way in keyboard lessons. Are you angry at the computer for not working, or at yourself for not being smart enough to figure it out?