Well, it depends on the threat model. If someone has the plan to search through a thousand hard drives belonging to a cross-section of random people, one byte a

Well, it depends on the threat model. If someone has the plan to search through a thousand hard drives belonging to a cross-section of random people, one byte at a time, looking for something of value, then sure - it might be worth the effort to corrupt someone at Apple. But if you are an industrial spy looking for a particular secret, or a personal enemy looking for data about one person, or an aspiring burglar casing a particular building - you look in the trash can belonging to your target. I think the latter threat is as plausible as the former.