I am certainly not an expert on self defense.

I don't think a pistol is a great self defense weapon unless someone spends sufficient time training and keeps the training up. Most people that I have trained start off having difficulty hitting a man size target at 7 yds.

The problem is aggravated by shooting small, easy to carry, pistols. Add stress, and accuracy goes way down.

On gun selection, a full size, loaded semiauto is easier in that one just pulls the trigger and plastic guns (Glocks etc) absorb some of the recoil. A DA revolver in 38 is doable in that, again, it is just pulling the trigger A SA requires more training, remembering under stress to cock the hammer.

A 38 with proper bullets can be effective. A 22 is probably more effective than a thrown vase but, unlike in Hollywood, not many people (or animals) when charged with adrenaline, stop fighting with a not much more.

Again, whatever handgun one selects, they need to practice, practice, practice.

Several people I have talked with recommend a 20 ga shotgun which is probably easier to shoot at 7 yds but again, good shooting requires training and practice.

Poor or lack or practice reminds me of a gun fight in La Casa del Los Marinos in the early 1960. Sailors from two warring nations (Greek and Turkey) met and a gun fight erupted. Police reported that over 50 shots were fired but nobody was hit.

Those are my thoughts.