I think this is where people draw the line. with a J frame they were "only" getting 5 shots but they could be .357 mags or .38spl +p. now, a smaller gun might be nicer but maybe not if you're going way down in power levels. the smaller D/A revolver have relatively stiff triggers compared to larger revolvers (save for the Ruger LCR). the trade off for smaller bullets has usually been at least you get more of them.
That's obvious. For decades the bare minimum has long been .38 Special, more recently it's .380 thanks to the advent of the polymer guns like the LCP, and anything below was inadequate.
Over time, science and technology is proving that wrong.
I'm not saying the .32 S&W or .32 SWL is perfect, it's not, but it's not as incapable as people have made it out to be and that holds true for the .32 SWL especially. There's a massive lack of data for the performance of .32 revolvers when used in self defense compared to more popular calibers.
The fact is we really don't know how the .32 performs on the street. It could be better, worse, or the same as .38 and we wouldn't know.
My issue with the .357 is it's horrible to shoot from a snub while for .38, save for a handful of factory options (Critical Defense, Golden Saber, HST) other ammo has difficulty expanding from a snub. Could I blow $80 and get a few boxes when it's available? Sure, but the benefits of the .32 with the lower recoil are still present.
Even with a .38, the power level from a snub is still far from ideal.
As to the size of a purpose built 5 shot .32 revolver, I see no reason to believe they couldn't have a trigger as good as an LCR, but be half the weight and dimensionally smaller.
What benefit that has is questionable, but the argument of having a gun vs no gun will still apply. If it's as easy to carry a little 5 shot .32 as it is a folding knife, whether it'll be a primary or a backup gun, everyone who is legally able to carry would carry and that would be a good thing and it would be better than a less reliable, less powerful .22 with a horrendous trigger.