A meaningless (and hence wrong) distinction
"Investigators are blaming human error for the data breach, rather than the system design".
But the human beings who operate the system are part of it. If a human operator makes an error of judgment, that is every bit as much a failure of the overall system as a hard disk crash or a programming oversight. The alternative - to exclude the human element from the system - is absurd, as virtually all systems include human elements who can easily make them fail.
Of course the people who are responsible for the system (and who earn really, really big bucks on account of that awesome responsibility) like to think that they can blame anything that goes wrong on the pondlife* who do the actual work. But it ain't so - they, the big cheeses, are equally responsible for hiring and firing the pondlife, and for motivating it, giving it adequate rest breaks, and generally making sure it performs up to specification like every other system component. Gee, if they are really concerned about its performance, they might even go so far as to try talking to pondlife occasionally. You can learn a surprising amount of useful stuff that way.
*Disclaimer: don't get overwrought about my use of this simple vivid term. I am pondlife myself, and very proud of it.