Raising your voice in excitement at a concert is completely and entirely different than yelling at your kid in anger. So is yelling at someone who has wronged or abused you. A child who has made a mistake fits into neither of those categories. You have a duty as a parent to guide and protect them - not to unload the weight of your disappointment onto their developing psyches. Yes, that shit used to be acceptable. So was beating your wife as long as you didn’t use a stick bigger than the circumference of your thumb — which is what the rule of thumb means. What we know now with modern psychology is that shit is abusive and extremely detrimental to children and families. Lashing out at someone you have power over in anger is standard dominance hierarchy fare, but it’s ugly and destructive. It’s NOT OK.