I’ve seen bird shot vs. human body at close range, it is ugly. It basically makes about 10 pounds of hamburger. If there is clothing in the way, it mixes the fibers with the meat. The wound is big and it is deep. Deep enough that even if dressed for Anartica, it is not going to make a big difference for the person shot.
the price/round of shotty ammo makes me want to be confident in birdshot for ‘close encounters’...