Apparently you have not a clue as to what the word "brandish" means especially when referring to a gun.
bran·dish
1 : to shake or wave (as a weapon) menacingly
2 : to exhibit in an ostentatious or aggressive manner
He had it slung over his shoulder according to the story and the police said he was legal.
He didn't "brandish" it.
And your reaction is why the gun grabbers can get so much traction with their "concern trollage" try not having such a knee jerk reaction and think it through.
He wasn't menacing or brandishing or any other thing. He was doing what the 2nd Amendment gives him the right to do, keep and bear arms!
Where in the story does it say he had it slung over his shoulder? Nowhere. I’m assuming then because he was there to ‘prove a point’ that he was displaying it ostentatiously, or brandishing it.
Bottom line - guns are serious tools. As I said, I grew up in the rural areas and guns are brought out to use, to clean, or to transport. They aren’t some neo-60’s hippie protest statement, and you don’t walk around with one to prove a point. He didn’t do anything illegal, but he sure didn’t use good gun handling protocol either. Like several said here, if I was carrying I would have had safety off ready to put the guy down if he made a wrong move.