First off, ditto what has been said regarding SOS systems. They came, they were found wanting, and they went (well mostly).
But, as I recall, there was a time when the procedure being taught for an SOS was to pull enough to cutaway, wait to confirm that the main had left, and then to finish pulling the handle. Now, why someone would stop after the cutaway and not finish the Emergency Procedure, I can only guess. Maybe they were waiting for an RSL to save them. But the concept of delaying between the two different actions of the SOS was being *taught*. It didn't just get invented by the hapless jumper.
So these events, though totally sad, were quite similar to the "cutaway and failed to deploy reserve" incidents that are still, inexplicably, part of the sport.