First, I largely agree with prior comments.
Side-stepping the discussion about the terminal ballistics of the 38 Special and focusing on the non-deadly force aspects of the cartridge – It is just a downright joy as a target cartridge. The 38 Special is also a bullet caster and cartridge reloader’s dream.
Compared to the bigger bores, it’s easier on lead and powder. The straight walled casings last nearly forever and they are easier to recover than casings from a self-loading pistol. The cartridge is very forgiving to reload but it does respond favorably when attention to detail is observed.
In today’s world there are better options for self-defense cartridges BUT that doesn’t mean the 38 Special is incapable of serving in that role, it just means there are better options. The 38 Special gets overshadowed a bit due to the excellent options now available.
The old 125 grain semi wadcutter, semi jacketed HP 357 magnum cartridges were, and still are, very effective self defense cartridges. This was classically exemplified by the old Federal 357B loading and is the standard by which all other 357 and 9mm handgun self-defense cartridges are compared to. The current crop of 9 mm rounds available for self-defense are the best we’ve ever had. The contemporary 115-125 grain 9mm +P, JHP rounds are very close to the old 125 grain 357 magnum cartridges. Yes, they fall a little short of the velocity of the 357 magnum from a 4” barrel and therefore have a little less muzzle energy. But that’s like saying a 95-pound anvil is weaker than a 100-pound anvil. They will both likely work just fine.
The 125 grain JHP 357 Magnum round has a strong and well-established track record as a self-defense cartridge out of a 4” or longer barrel. It gives up a little velocity in a shorter barrel but not enough to really matter. The current 9mm +P 115-125 grain JHP rounds are very competitive to the 125 Gr, JHP 357 Magnum AND have the added benefit of the platform they are launched from (higher capacity in the gun, faster reloads, work well with shorter barrels, and more compact guns in general).
Leaving the cartridge war discussion again – the 38 Special is just downright FUN for a reloader and recreational shooter. And, while perhaps a bit outclassed by current options, it remains a viable self-defense cartridge.