It just floors me that he didn't come to a complete stop before disembarking the locomotive.
As people have mentioned with modern systems there is rarely one single point of failure. It usually requires the failure of multiple systems in close succession.
In this case the rails were slick with rain, the switch was erroneously in the wrong configuration, the engineer misconfigured his locomotive in haste, the engineer dismounted a moving the locomotive against policy, the engineer failed to board the locomotive due to the wet handholds being slick as well as the train picking up too much speed, and only then did they have the full on runaway train.
Changing any one of the above variables and there is no incident.
Plus he was acting in haste, and therefore not thinking it through.
Another train caught up with this runaway train, coupled to it, attached the air brake hoses, and applied the brakes.
This slowed the train to a crawl. Then an engineer was able to jump aboard and cut the power.
The only damage was the burned out brakes on the locomotive.
Most dump trucks have alarms that will go off if the bed is raised while moving and some modern ones can even limit speed while the bed is raised (there are plenty of legitimate uses for driving slowly with the bed up), yet it seems like we don't go a month without someone slamming one in to a bridge.