Yet your conclusion, spoken as if it is a universal truth, is wrong in many instances.

There have been numerous events of a concealed weapon holder killing an individual intent on a mass murder event that's just getting started. They generally get zero media play because they don't fit the narrative of gun -> bad.

Regardless, telling people they can't choose the means with which they can reasonably defend themselves is authoritarian and evil. Nobody can guarantee safety, thus, nobody can rightly deny the right to defend oneself how best it seems to them to do so. Some dangerous circumstances are unfortunately common which do not wait for the police, let alone courts.