Do we know he was "open carrying"? I may have overlooked the part that specified. It's an easy assumption to make but I didnt see anything actually specifying that?
That said, after seeing all the videos of people attempting and sometimes succeeding in taking away LEO's pistols it should give gun carriers pause. In the "Law Enforcement Officers Killed and Assaulted" from U.S. Department of Justice database we see that about 10% of LEO's killed and injured with firearms occur with the LEO's weapon. I doubt if the typical gun carrier would fair any better if a bad guy attemptd to gain control the weapon.
But as I said, if you want to, do it, you'll get no flak from me.