What a twisted web we weave.
I took a look at the reference which states:
"Destroys the given pool, freeing up any devices for other use. This command tries to unmount any active datasets before destroying the pool."
So I don't see where it states it's not really destroyed but I do believe you. I have been confused once before about this evil play on words. I also thought that when the Devs wrote this that when they destroyed a volume that they wrote to the front and back of the drive in order to make it look like no data was present. I'm sure I'm confused there as well, it's late and I'm old and tired. Nope, not drunk but give me time.
But I would like an easy option to physically erase the data on the drives. I'm not looking for a DoD Declassification feature, if someone wants that they would likely have to use a specific version of the software approved for that use. Us home users don't really care that much, but if we did then we are probably up to no good.
Cheers!