some small percentage of the data will still be around, because they do overprovisioning.
That’s why I wrote “directly accessible data”. You are certainly right that safely erasing all data on SSDs is hard to impossible to achieve, but so is the read access to it.
That means if we disregard the drug distribution or similar scenarios, should be enough for the normal person.
But I mean secure wipe isn’t hard… It’s copy-pasting 2 more commands from the Arch wiki, compared to the dd command.
But it will take significantly longer (typically using /dev/random and multiple passes) without noticably increasing security for SSDs.
It will have also have the same possible write-speed-penalty issue as the zero-overwriting, but this won’t be OPs problem any more because he is selling the SSD.




The devices in question all were fat formatted, for which it is quite easy to reconstruct most of the “deleted” content using readily available simple tools (which I did).
But that was some time in the past, nowadays most systems use some kind of base encryption, making it less likely to easily find something.
The phone, on the other hand, was just not doing a factory reset before selling it, but only deleting files (and missing stuff, like some mail folders) and not having a password-protection at all… 😬