In post #66 i give 2 examples of what i'm talking about.
Right there in your second example is the following:
"Use of force and firearms expert Emanuel Kapelsohn told NBC News that, from his understanding, the man who took down the shooter reacted appropriately.
"I think it's to be applauded," he said. "
Not everybody in the world ought to own a gun. Not everybody in the world ought to carry a gun. Not everyone in the world ought to engage an armed criminal where innocent people could be potentially injured."
"But this good Samaritan obviously had the ability to do what he did," Kapelsohn added. "Who knows how many people would be dead if he had not acted?"
I totally agree with the expert here and would argue that a minority of gun owners have this ability.
In your first example - the gunman had mental issues and was previously known to police (who had been warned about the gunman by LGBTQ groups) - so it's as much an example of a failure to treat and prevent. Further the gunman was licensed to carry and worked as an armed security guard - despite his mental issues - which opens up an entirely different debate.