That quote sounds good, but I don't think it's necessarily applicable to this situation. The author seems to be talking about complex systems that are designed and operated to be robust against failure, like the space shuttle. Saying that Challenger blew up because of an O-ring is technically correct but also horribly wrong, as an example. Equifax IT does not appear to be operating at a level to prevent a single failure from causing terrible damage all on its own.

That aside, it's hardly true that one person can bear all the blame for not patching their systems, even if they did successfully prevent patches from happening. For one thing, how the hell did they keep their job after doing that? Unless it was the CEO (well, now that they have a new CEO maybe they'd like to put all the blame on him), there was someone up the chain who could insist that the patch get applied. I think you definitely could apply root cause analysis techniques here, and I strongly suspect that such analysis would uncover numerous serious deficiencies in Equifax's IT operations. Of course, guessing that a large boring corporation has terrible IT practices is similar to guessing that a given duck quacks and has wings, so there's that.