This is "exhausting" for you, Solo, because you wish to keep arguing about irrelevancies that prove nothing. Coulda, shoulda, woulda.
If he had kept driving he MIGHT still be alive. If he had carried his gun he MIGHT still be alive. If he hadn't left his house to drive down that street with his daughter, he MIGHT still be alive.
It's irrelevant to conjecture that he MIGHT still be alive. Whether there's a "small, tiny chance" that his firearm MIGHT have made a difference, is irrelevant. He's dead, gone, finis.
I managed to "comprende" all that long ago in this thread.
Just how are you "sure" Mr. Pettit was wearing a holster that day? It hasn't been established that he was on duty. After all, he's a POLYGRAPHER, and they don't usually administer lie detector tests to suspects while driving down the road with their daughters in the car. I also would be willing to bet that most polygraphers don't take their daughters to work with them.
Also, many LEO's and civilians own clip-on IWB holsters that allow them to remove the gun AND holster while in the car, for comfort purposes. So it's entirely possible that Mr. Pettit had both gun and holster locked away in his glove compartment, especially since he was with his young daughter, who he certainly wouldn't want accessing his firearm.
Being fifty two years old and apparently having a bit of a temper himself, there's a good chance this wasn't the first time he'd ever engaged in an exchange of vulgarities and middle fingers with people in traffic.
So he has an exchange with Mr. Wonder, who appears to be a harmless old man driving a fairly nice car, coincidentally it was the same make and model as Mr. Pettit's car.
So he's PROBABLY thinking something along the lines of "Old guy in a nice car driving like an idiot, he's not any kind of threat---I think I'll stop and give him a piece of my mind, especially since he flipped me off with my kid in the car."
Alas, Mr. Wonder turned out to be an emotionally unstable individual with a gun. End of story, at least for Mr. Pettit.
I'd be willing to bet that A LOT of other individuals, both LEO and civilian, would've made the same mistake as Pettit, in underestimating an "old guy in a nice car".