it just securely overwrites the sector containing the encryption key with a new one This technique isn't just for SSDs. Something similar can be used with norm

it just securely overwrites the sector containing the encryption key with a new one This technique isn't just for SSDs. Something similar can be used with normal hard disks. Just store the true key as metadata on a hard disk. Erase the few sectors of metadata and the disk is no longer readable. Apple's FileVault 2 does something like this. https://www.lightbluetouchpaper.org/2012/08/06/analysis-of-filevault-2-apples-full-disk-encryption/ https://www.lightbluetouchpaper.org/2012/08/06/analysis-of-f...