There is a lot of talk about provocation.
The fact of the matter is, all the way from getting the wrong order at a fast food drive-thru, to being asked to be quiet at a movie, we know that certain recognizable people are provoked very easily.
Absolutely, every disagreement may be provocation in hindsight. As I noted, as an old man I might well be in fear of my life were I thrown to the ground, particularly with a second youth approaching at a fast walk (see video) to my left. Add to that the risk of losing his weapon in a physical altercation. The problem the shooter will face here is both his past history of loud complaints, and his purported verbal harassment of the girlfriend. Which, imo, might merit a verbal attack, but not physical as the coach did. We really don’t know all the facts yet, but I can see where the shooter could have a problem. He clearly has a substantial legal bill. My opinion only, I’d have stayed in the car. Call the police if you’re upset. Don’t put yourself in a situation which can escalate needlessly.