I have no reason to doubt your experience, it's just that most deceased have relatives and they're the ones who report the death.
SSA will only get the death certificate if someone sends it to 'em. The important thing is to report the death since some death certificates can be agonizingly delayed ( you can imagine why)
Seems like a haphazard way to do things. Who is legally responsible to report the death or remarriage of an alimony recipient? It's no wonder why SS and alimony payors are going broke.