I will echo the sentiment that kids tend to exacerbate things. Now, I am probably over-thinking this, but I have done some deep dives on my own anger. My conclusion is that our current environment is such that we feel like we cannot say "no" - to bosses, spouses, the people who sell us stuff, etc.
What does this have to do with kids? They have the power to say no, to us and to all other authority figures in the world, and have not yet learned otherwise. I hate using "trigger" as a word, but hearing kids say no is triggering. Why? Because it reminds us of a freedom we feel like we don't have, or feel like we have been forced to give up in order to have a safe, easy life. The problem is that life is no longer safe nor easy, as evidenced by the last three years, and our sacrifice was for nothing. Now we are stuck with the consequences of not saying no.
The truth is, however, that we can say no, and we could have done so all along. And, the cost of doing so is not as great as what we catastrophize in our minds. It is hard to say no, because we have been trained not to do so. And, when we do finally crack and say no, we deliver this simple word with the weight of years of resentment and anger behind it, such that we come across as a psycho.
When you realize that most of the worlds' current problems are the result of narcissists building a system where nobody can ever say no to them, it can be both freeing and terrifying. When you realize that every angry display you make is a way to say no without having to actually have the courage and vulnerability to simply say no, you start to see your role in this toxic system.
The lesson? Grow a pair and stand up for what you want. Doing so makes you better than the hordes of billionaires who do crazy things like become President, buy Twitter, or build online retail monopolies, all in the hopes that they will become so powerful that nobody can say no to them ever again.