I see this as an important lesson to gun users. Knives are a superb complement to having a gun, especially in a close quarters situation, in the defense or the offense.
In the trench warfare of World War I, soldiers quickly realized that the ideal weapons for fighting in trenches are a pistol in one hand, and a trench knife in the other. If the enemy is at a stand off distance, use the gun. If they are in your face, the knife is better.
And being indoors is little different from a trench with a ceiling.
Importantly, movement outdoors in a riot, mob, or “wilding” is much the same. Instead of walls, you are surrounded with bodies. Some are the enemy and some are indifferent.
But if the mob turns on you, you have very effective stand off distance with them, and might even change the flow of the mob away from you, with a pistol and a knife.
Goin' to Black Mountain with my saber and my gun;
Cut you if you stand, shoot you if you run.
I carry a strong yet inexpensive 5 foot wooden walking stick with a metal point at one end almost everywhere in lieu of a cane. People forget that a quarterstaff beats a fists, a knife, sword or even firearm in many cases. Watch the Steven Seagal movie with the hillbillies or the Clint Eastwood one with the gold prospectors for examples.