You say all of this as if you've never interacted with a young child before. My nephew is about 2 and a half years old, and his parents don't spank him, and every time he is told to do something he doesn't like he cries or screams or just ignores what he is told. Doesn't matter if his parents give him the practical reasoning behind it. It's not that they don't understand speech like you strawmanned, but rather than they don't care about reason or logic. They care about avoiding what they don't like and getting what they do like, and that is pretty much it. Children become spoiled when they are taught that if they misbehave then their parents will have to offer them something good to get them to behave. That causes them to misbehave more. If they are consistently disciplined, then they don't misbehave as often. Sure, you can try time out, but that isn't going to work for long before they realize that they don't need to listen because all you will ever do is tell them to go back to time out. Taking away toys or other privileges also goes over like a lead balloon. Better yet they later forget about those toys being taken away and will throw fits yet again after asking for them and you tell them that you took it away.
So you would then suggest that parents just let their kids do whatever they want whenever they want, because disciplining them just encourages them to hide things and lie?