The mistrust in Coinbase line of thinking seems similar to fear and paranoia about terrorism. Could a bad actor acquire and use agency to do something horrible like obtain a dirty bomb and set it off? Sure, it is possible. But at the same time it is very unlikely. People GENERALLY want to be good actors and make a positive impact on the world.

With Mt. Gox I am more inclined to think their problems stemmed incompetence rather than malevolence.