The only problem with that is they would probably charge you with murder and the woman would condemn you for shooting a poor black man as she was a BLM supporter.
Well, that along with the fact that Coach is not in any way distinct from the 'majority of people' who see something like a frenzied knife attack on a woman and freeze. Given that he has never been a paramedic, policeman, or well-trained soldier, it's rather far-fetched for him to propose that he'd leap up like a coiled spring from his bus seat, immediately double tap the bad guy, and then control a catastrophic bleed from a woman who's just been stabbed three times in the neck and severed her carotid artery, thereby saving the day.
The incident was truly depressing to read about, and the POS should have had his brains blown out long before it even happened, but I doubt it would have played out any differently with Coach on the bus. You'd have probably just ended up with a second casualty from him inhaling his Big Mac as he gasped in horror.