The point was that human life just like any living thing can be extinguished by the smallest of things. At 20ft which seems to be the agreed upon interior limit of most shots one would likely encounter inside a residential structure, both loads would have a high component of lethality. One just offers a much less chance of collateral damage.
I for one would rather not kill a bad guy in my home with buckshot and walk into the next room and find that I had also killed my child or wife. Others might disagree but again and for the last time it my personal opinion and a choice I hope to never have to make.