I think it's also meant to protect from potential mistakes in handling of hard disk decommissioning which presumably is a common thing with data centers.

Used to be, but e.g. where I work any decommissioned drive has to be DBANed (if it's spinning platters) or secure-erased (SSDs). If it can't be for some reason (e.g. it has failed) it needs to be physically destroyed. I would hope most data centers have similar policies in 2026, but that may be optimistic I guess.