

It’s called the ultimatum game and we know how actual people play it.
You’re given £100, but you have to offer some of it to me. If I don’t accept the offer we all get nothing.
We know, because we’ve played the game a bunch of times, if you’re greedy and don’t offer enough I will punish you. The Dems/Harris was greedy, and as such everyone was punished.

The audiobook? The answer was contained in your question. The result varied by type of drive though. They improve drivers during boring drives and well:
I thought I saw another study some yesteryear about spacial reasoning tasks demanded by some audiobooks (describing a scene, what a building looks like, where it is etc) impaired spacial reasoning while driving. While music doesn’t use spatial reasoning hardly at at all. That’s why I stopped using audiobooks while driving, but I can’t find it so maybe I’ve been lying to myself all along.
The takeaway: boring drives secondary tasks could be good. Complex drives secondary tasks could be bad. I’ll stick with music but be more readily muting it for potentially interesting interactions. In a use the secondary task to keep focus and identify the hazard, once identified mute secondary task to react to the hazard.
But I play focus games while driving anyway. I don’t indicate out of habit: I reason if there’s someone to indicate to, then decide whether to indicate. I find it forces observations and space/speed reasoning to infer whether my changing direction presents a hazard to someone somewhere.