The hard problem is, it never crash so obviously like the author charmingly presented as echo c > /proc/sysrq-trigger.

When something went bad(mostly hardware or rare edge case bug on software), it works mostly fine but randomly fails and no amount of hard coded sane checks can automate the detection. It either not crash(unusually slow or garbage result), or crash but it happens rarely enough to never go beyond the threshold of supervisor's restart strategy, so the supervisor keep restarting the unstable process rather than crash and let the parent supervisor know to remove itself from the cluster of nodes.