I honestly don't understand why people want to sit in traffic. I usually live in places that traffic is low enough that it's still moving along. If I saw this happen, I would strongly consider taking Uber, or public transportation (with e bike and good cable and storage) over sitting in traffic. Most of them are going to work, and usually have no need to carry anything. It's crazy to me.
The horn is the forbidden button, I've only used it once in my life. Although I do wish we had like a "friendly" horn I could honk if somebody left their blinkers on, or their gas metal plate thingie open...
Where I live a light tap of the horn, as short as you can make it, is a polite "wake up", a quick flash of the lights is also used to tell people their lights are off or another thing is wrong.
No, this is mostly a Hollywood thing to indicate that the traffic is real bad and the driver is real mad. The reality is that birds aren’t allowed to drive, and probably wouldn’t even want to.
Yes, I used to work in a building in downtown SF that was "historic" (old) with windows that actually opened, and every week day starting around 4pm we'd all close the single-pane windows to slightly quiet the irritating honking that was 17 stories below us. It was still audible but a good pair of headphones had a chance of being successful.
All it ever took was one person's honk to start a chain reaction that would go on for hours.