In every normal country this couldn’t happen because that guy wouldn’t have a gun in the first place.
Are you referring to a shooting in self-defence by a law-abiding gun owner? If so, then yes, if said law-abiding citizen didn’t have a gun, then, by modus tollens, they wouldn’t be able to use a gun in self-defence.
It would have ended in a fight or in the shooter suing the prankster and getting a lot of money while the prankster would be told by court to stop this stupid pranks.
You state “ended in a fight” as if that implies that the total damage imparted on both parties would be less overall. You completely miss the fact that physical violence can quite easily end fatally.
At any rate, wouldn’t a victim defending themself successfully, efficiently, and likely without bodily harm to themself be preferential to the possibility of a violent and bloody physical beating with odds likely not in the victim’s favor?