My interpretation of the OP's inference, is that buckshot, with multiple projectiles, carries significant liability (perhaps additional liability?) when used in certain environments/conditions for SD/HD or possibly LE. My impression is that he frowns upon that load for that reason. That is my interpretation of his intent.
A friend uses the expression, "Every bullet you shoot has a lawyer attached to it". Certainly true in this day of litigation.
My thought is that most SD/HD and LE shootings are still relatively close range affairs, well under 7 yds for the most part. At that distance, any pattern, from any barrel regardless of choke, will still be fairly compact, say 20" or so. Who knows what your fight will look like? But the numbers are there and have been pretty constant over the years.
Effective range v. maximum range, v. lethal range, are three different concepts. I've seen a lot of OO buck shot at agency qualifications back to 25 yds, and experimented with it out to 100. A OO buck is lethal farther than many realize, catch a pellet in the temple at 100 or more and you're done, but effective range for SD or hunting (deer) is likely about 25 yds in my observation, and max range no more than 50.
My own practice, when the only long gun available to me on patrol was a shotgun, was to load with slugs. Buckshot performance on barricades and cover, like auto glass and sheet metal, was not encouraging. At home, as I do not think I will encounter an intruder in the bedroom hall driving a Ford, my shotguns still carry buckshot, #4B or OO both acceptable.