Well, hell; given the choice in a self-defense situation I’d take the 12-gauge, too! :)
As for the handgun cartridges, placement is the most important thing. So, if someone can shoot the .38 Spl accurately and regularly, he or she is better served than if he or she had shot a .357 magnum or a .45.
I shoot .357 magnum very accurately from a 6” barrel, but in single action.
Mr 12 gauge 8 shot pump is hanging on the bedroom wall,ready for action.I really like shooting handguns,but I’m reaching for that model 500 marine If the SHTF.