Another one of these perennial threads.
I voted .38 Spl. That's me.
I own more than half a dozen J-frame snubs and a pair of LCP .380 pistols. I carry whichever is most suitable for the day's activities and circumstances. That's me.
I train, qualify and practice with both. That's me.
What should someone else choose to carry if only comparing those 2 "minimal" calibers?
Dunno. I'd want to see that person demonstrate their abilities using each, in a variety of basic to fast-paced and demanding drills, and discussing carry method preferences and needs. Might have a recommendation afterward.
FWIW, I've seen my fair share of skilled folks who could use little .38 Spl snubs and .380 pistols better than other folks who carried "full-size fighting handguns", but the folks carrying the larger guns still thought they were somehow "better prepared". Misplaced confidence? Perhaps.
As an armorer for a variety of pistols, and S&W revolvers, I have a passing familiarity with the advantages and disadvantages of each from a maintenance and operation perspective.
As a LE firearms instructor, who also spent 10 years volunteering to work with private citizen shooters (CCW licensees), I have a passing familiarity with how some folks are willing, and others unwilling, to invest more time and effort into meeting more than some "adequate" level of demonstrated skill.
Rather than obsess about (or casually dismiss) the importance of gun/caliber choice, I'd like to see more folks carefully consider whether they had enough knowledge, training, experience and the ability to make good decisions under stress ... than just rely upon some admired or popular choice of gun/caliber/ammunition.
Knowing
what to do,
why to do it,
when to do it,
how to do it and
being able to decide to do it (in sufficient time)? Potentially more complicated and risky than just choosing some gun/caliber combination.
Not everyone is necessarily going to be as well served by one particular decision as the next person.
Everyone is going to have to face the likelihood of having to try and live with their choices, and the consequences of their choices.
I'll continue to carry either a .38 Spl J-frame (including using +P in a pair of M&P 340's, even though they're chambered for Magnum) or a LCP .380, depending on circumstances and my assessment of practicality versus potential risk factors ... or one of my larger 9's, .40's or .45's, if the assessment makes me consider the little .38/.380's are less appropriate choices for the circumstances.
I'll continue to use all of them for practice, quals & training as long as I'm able to do so.
Suit yourself, for the reason(s) that seems most prudent and reasonable. Try not to fool yourself and think gun/caliber choices will somehow mitigate lack of attention to maintaining sufficient knowledge (laws, tactics, maintenance, etc), training, practice or mindset.