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> Understanding this is also quite important because it can have performance implications

Security implications too. The storage device cannot be trusted to securely delete data.

If you write whole drive capacity of random data, you should be fine.

No. Say a particular model of SSD has over-provisioning of 10%, then even after writing the "whole" capacity of the drive, you can still be left with up to 10% of data recoverable from the Flash chips.

Right, so one better write 2x or 10x drive capacity of random data to it.

You should be running flash with self-encryption (and make sure you have a drive that implements that correctly).

To zap a drive you ask it to securely drop the self-encryption key. The data will still be there, but without the key it is indistinguishable from random noise.

Well who has time and energy to verify that. Just overwrite it several times, or destroy the drive.

For some family photos? Probably. For sensitive material or crypto keys? Absolutely not, due to overprovisoning as mentioned (which can be way higher than 10% for enterprise drives), but also due to controllers potentially lying to you especially when drives have things like pSLC caches, etc.

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