I use Linux and it’s built in to my desktop environment. I just create a new vault.

If that malfunctioning drive was not encrypted you need to break out some heavy tools tool ensure that data is destroyed.

If by heavy tools, you mean a screwdriver and an angle grinder, then yeah, but it’s not that hard in reality.

I don’t encrypt my entire drive, but I do have encrypted directories for my sensitive data. If I did encrypt an entire drive, it would only be the drive containing my data not the system drive.