Why do people find hyperactive dogs dangerous, where's the proof in that?

I think people overexaggerate hyperactive dogs are dangerous and will kill by being excited. They tell their dog "Shut up and be quiet!" Would you tell your children or children that are not yours "Shut up and be quiet!" when they are excited? I been with dogs for a long time and my personal experiences never seen dentrimental of excited dogs. There is no reason for anybody to not be excited and not to be happy. Anybody who does not be excited are missing out. Those who are excited are not missing out anything. Imagine if your loved one child, husband, wife, partner you haven't seen them in a certain period of time. They came back from war or something else and somebody was forcing you not to be excited because you are disrespectful. I find that messed up.