Guess I decided not to get involved in this thread late last year, as I didn't see it listed as something to which I'd contributed.
Okay ...
The idea of a "pocketable" defensive handgun is not without a lot of variable definition, usually because it's considered differently from the perspectives of different people. Not uncommon, right?
So, from
my perspective and experience ...
If I don't feel the day's risk assessment merits belting on one of my 9's, .40's or .45's, or one of my .357 or .44 Magnum revolvers ...
... I've typically, over many years, settled on one of my several 5-shot J-frames.
Starting back about 2012, however, I reconsidered the newer plastic .380's, and the newer ammunition, and decided to add a Ruger LCP to my retirement CCW stable. Then, I later added a stainless version of the LCP.
The LCP's fit in a number of shorter & tighter pants front pockets in which I can't carry or conceal one of my .38/.357 snubs. Since I've reached the point in my life where I'm no longer quite so ready to "dress around" a handgun (having carried one with one or another badge for just over 34 years), the little LCP's suit my occasional needs for a low profile, easily pocketable small caliber defensive handgun.
Sure, I prefer the heavier bullet weights of the .38 Spl, but this is one of the "choose your own compromise" situations and choices.
Additionally, in recent years I've pulled an older NAA .22LR from the safe, which I'd not carried for close to 20 years ... and I've added a short 1 1/8" NAA .22MAG, and a Black Widow 2" .22MAG w/.22LR convertible cylinder.
I consider the NAA mini revolvers to be mostly a supplemental, last-ditch "Onion Field" hide-out gun. (Look up the Onion Field incident, if you're unfamiliar with it.) Other folks look at them more as gentlemen's pocket jewelry, or a novelty. Easy to understand those perspectives.
I also grew up learning to shoot revolvers using SA revolvers, so the added manipulation of the NAA's doesn't seem bothersome to me, although other folks can certainly have other opinions and experiences. That's what makes a horse race, after all.
FWIW, there are some interesting modern ammunition developments in the .22MAG that offer some edge in utility, such as the Speer .22MAG Gold Dot, specifically designed for a 1.9" barrel.
Handguns are a compromise. Where you want to start making the compromise is up to you.
Personally, I'm not interested in a .25 ACP or .32 ACP, but that's
me. I'd also not care to carry a .22LR semiatuo pistol, as I've seen my than my share of them fail to function during normal range training quals over the years, even the best makes/names. Granted, most stoppages seem to be related to poor owner maintenance practice (dry/no lube & dirty), but QC of .22LR ammunition can be variable, too. (Lacking enough power to cycle a slide isn't a problem with the mini revolvers, of course, but poor priming/manufacture QC can still be a problem.)
I sometimes use a LCP as a secondary to a snub or larger belt gun. Sometimes one of the NAA's is the 2nd or 3rd gun being carried (that 'hideout' for an Onion Field scenario).
The snubs and LCP's had to demonstrate their practicality, controllability & accuracy in the same off-duty/retirement qual courses-of-fire as my larger handguns. The NAA's are used within the ability of their slow rate of fire, but not out to much more than 7-10yds. Mostly I envisions their usage at 1-3yds. Extending the range of a punch, so to speak.
If I were to return to working uniform or plainclothes, being freuqnetly placed into high risk situations throughout a day/night, the smallest secondary weapons I'd consider to back up my primary handgun would be one of my J's or LCP's.
Then "best" in category? Not something that's definitive across the board. Going to be up to the individual. It' still just a handgun, after all.
Just my thoughts.