Well, the guy that I saw in the video, the red car that got shot at and pulled over just a few meters past the active shooter stopping FAST, he died it seems.
This goes back to what I posted yesterday. If he cut off my escape or he hit me and disabled me from completing my escape, I think I would have engaged him. I can't say for sure, I wasn't the guy that got hit, maybe he got hit in the neck and was paralyzed. But from what I saw, were I in the red car and still capable, I probably would have taken him down. He was certainly close enough in an open intersection for me to accurately put a couple 10's in the chest. That would have stopped him from shooting several other cars and/or people.
But in CA, the law abiding citizen does not have this recourse. That guy in the red car pulled over because he was now disabled and was stuck in the street that way with an active shooter. Since he's in CA, he has not weapon with which to defend himself. The law has abanonded him and declared his right to life and defense of it non-sequtr. In CA, this is allowed to go on until the cops show up. It can take them minutes, it can take them seconds, but you can do a lot of damage in a crowded place in just seconds.
I think that a criminal just knowing there is a large community of concealed carriers significantly drops the chance of it happening. Some will do it anyway, but others, the ones that want to get away with it, they'll think twice. In WA, we are shall issue, and lots of folks carry here, mostly concealed, but some open. You almost never hear of a CCW holder in trouble or involved in something bad. From time to time, the news will say a guy was robbed or broken into and defended himself and that is pretty much the end of it. Prosecutors don't like charging folks involved in obviouisly justifiable homicide cases because if they lose, the state has to pay for the entire defense bill (but one clown wants to change this, has a bill that probably won't pass).
We have our problems, we had the Tacoma Mall shooting. But the story there to the bad guy is that if you try that crap, some dude might jump out from behind a rack of levis and let you have it when you least expect it. It ended bad for the good samaritan, but it doesn't always end that way, and by that guy getting into it with the bad guy, he very well could have bought others seconds and saved their lives.