Alright, so the thing I never understood was, how people justify this--or any really--level of suspicion and force with "they could have a weapon". It sounds logical so I get why it's a commonly said response, but the simple fact is, when people have weapons, they don't wait until Police Officers get close and start chatting with them to make that clear. Look up any video of Police getting shot at, and almost always it's someone barreling out of their car firing as fast as they can, or a cop walks up and the person immediately starts firing. I have never seen a video where there's any real delay between them being in proximity and the person firing--by contrast all the videos of police shooting unarmed people, it's usually after several seconds or even minutes of them issue commands.
If someone has a weapon, they aren't going to risk being shot before they get a chance to use it, so why bother using that excuse? It just doesn't fit with the way humans interact with Police Officers historically. Look at the Dallas shooting, did the guy get stopped by Police and then start firing? No, he preemptively took a position and started picking them off with the element of surprise. If people are going to try and go toe-to-toe with someone who they know is also carrying a weapon, they are going to want to have every advantage possible.
This guy hopped out of his car and ran into the open--this tactically is the worst thing he could have done, and right there should have given away that he wasn't actually a threat. But Officer Donnie had already gotten out of his car and drawn his weapon, so he had decided the guy was a threat. The problem isn't "it happened too fast", it's that the Officers mind was made up before he even got over to the guy--this is the flaw with the way Police Officers conduct business in this country. They are trained that anyone doing something other than completely complying while being white and fearful, is a potential threat.