Every single trainer I’ve been with is against open-carry.
The thug noticed, he chose poorly, but it could have ended a lot worse for this woman.
It’s always better to be gray then black or white when it comes to CCW.
Strategically, open carry has many advantages, the primary one being that it fosters a general awareness of an armed society.
Tactically, concealed carry and open carry both have advantages that are different.
Most firearms trainers train people to obtain a concealed carry license. That is another reason they focus more on concealed carry. There are even a few states that prohibit open carry. (precisely 5, but there are others that effectively prohibit it through extra-legal means)