Part of me does not like guns because as a 200lb male I won't be pushed around easily if there is no gun pointed to my head, so I can definitely see what you mean by equalizer. However even a hand gun can be grabbed away, if the muggers are bold enough.

I would argue that the best solution to that would be a silent alarm that can be easily triggered (ie as a cellphone app) and a fast responding police. Second best solution would none lethal deterrents like pepper spray.

I also think it is a false narrativ to believe that if guns are outlawed the criminals will have the advantage, because they are the ones using guns. This might depend on the society though, what works for us in Germany might not work over in the States.