back in the 1970s I learned that the 200gr LRN (then one of the "standard" loads, and carried by a lot of detectives) fired from a snub nose would not reliably penetrate a car windshield at point blank range!
The solution was simple, first, don't shoot the 200gr load at car windshields.
Second, if you do need to do that, find something that works better.
Some people just can't seem to wrap their minds around the fact that something that isn't the best tool possible isn't automatically useless.
Picking cases where the .38Spl failed is simply picking cases where it failed. EVERYTHING has cases where it failed. There is no magic bullet.
I can point you to a case where a man took 33 9mm torso hits before going down. Another man took a pair of 12ga slugs to the chest and ran away (he didn't run far, but he ran). Another case of a woman (cop) taking chest hit from a police .357, and still winning the fight.
my personal urge would be to give that gentleman in a suit a parting shot, something on the lines of "Hmmm, so by your reasoning, all the people killed with .38s aren't really dead then?"
Have a nice day!