Yes, this run-away train of consuming beyond our means is quickly approaching the end of its track. However, using the analogy of a run-away train has other implications.
If the train's occupants get off, does the train continue running down the tracks? Is getting off a moving train easily accomplished? I understand it may hurt somewhat. What about the people that set the train (read: economy) in motion along its course towards destruction? Is there any reason to believe that destruction has always been the goal? Are there passenger cars attached to the locomotive - what about the people who don't get off?
Just some thoughts - these questions are rhetorical for the sake of the example. I find the comparison to a train attractive because of all the other factors that may mirror so called 'real world economics' - which, as we are seeing, are nothing more than illusion.