Given the accuracy of the average police officer in hitting a target under stress (numerous reports and statistics) vs a highly trained knife fighter, I can see the knife winning.
However the average Joe with a knife vs a man with a gun, how many stories do you see where a grandma grabs a pistol and blows a bad guy without a gun away? Fairly common.
I carry a .380 and it is not very accurate beyond 10’. However most confrontations are at 10’ or less. While I can hit the center of a target at rifle distances with my .357, I am not going to be defending myself from an assault by knife at that distance. And if some nutcase is charging me at that range,I will have plenty of time to shoot him.
As to the .22 short pistol, you put several into someone, a 22 should work just fine.
If packing this gun is about concealment and weight and an individual is set on 22 caliber why not the 22LR? I believe this handgun is also made in 22LR.