You would be surprised. MTBF (Mean Time Before Failure) ratings on hard drives have grown to the order of over 1 million operating hours on average. Hard disk drives can withstand up to 300 Gs of impact without affecting the integrity of the spinning disks. Scratching a physical disk is nearly impossible without opening the case, which voids the warranty on every brand of disk, and even with an open disk enclosure, data can be recovered.
The only surefire way to destroy a hard disk drive is with thermite, or an analogous high temperature. This story of hard drives failing all over the place is ludicrous and an insult to the intelligence of not just IT professionals but the American public in general.
The public just gets bits of second and third hand info. Last I heard there were 7 people related to the investigation had issues with their HD. Now it might be 20. If the numbers are accurate, it is hard to believe they all had hardware equipment failure. Is something like that even possible? I'd say yes, but highly improbable. I've been in IT long enough to see bad equipment batches from vendors. I haven't seen any report or heard any testimony that suggests that is the cause. One thing I haven't heard or seen mentioned is what they were doing about patching systems and virus mitigation during the time period in question. The commissioner has been pleading poverty, so I wonder if those efforts were substandard. That hasn't been used as an excuse either.