What ever happened to punching someone in the nose? Or wrestling with them? Such incidents are usually very short-lived and result in little injury or death.
Most men would RETREAT from such a situation, or get out and FIGHT LIKE A MAN, rather than bring out the gun and KILL the guy. Seems like a bit of an escalation to me...stopping a possible battery, usually a misdemeanor, by killing someone.
Every time an incident such as this one happens it's more argument to take away gun rights-in particular, carrying one in the car. You'll see...
When your only tool is a hammer, every situation looks like a nail. Or whatever..
I have a large Magnalite in my car, pepper spray on my keychain (Fox 5.3), and my FISTS. There's also the car door, windows, locks...if guy had time to go inside the vehicle and get his gun and come out again he might have a problem with the authorities. I don't know if there's a duty to retreat law in Florida for such a situation or not. He'd likely be charged with manslaughter in other jurisdictions.
Assuming the deceased was not carrying any thing that could be construed as a deadly weapon, this motorist may be in real hot water-maybe criminally, but certainly civilly...of course, depends on the facts, which we don't really know.