What exactly is done in the panel?
Guns have a certain place in American culture, storytelling (movies, shows, etc...)
but since they are so regulated in Japan, access to them is a lot more rare. Thus, animation studios often rely on more extensive hearsay or imaginative extrapolation. We also bring in and compare manga in which firearms are depicted to comic or otherwise noteworthy effects.
Like bringing an assault rifle to school.Or a pair of MAC-11 machine pistols.The panel discusses how characters are using firearms in anime, what's new and different,
and also common tropes and cliches we find amusing or unusual, or entertainingly exaggerated.
Anybody want to bet that in the scene where this girl raises up the rifle, the studio added a sound effect of:
(a) the slide of a semiauto pistol being racked,
(b) a pump-action shotgun, or
(c) a bolt action rifle being cycled?
(All of which would be unnecessary; refer to
THIS TROPE.)