The detail about the firmware not being able to deal with empty sectors is very relevant to ZFS.
You might be asking "but scrub/resilver doesn't read from empty sectors!". Well, they can, if they're issuing a large read that happens to have a small bit of something else (data or empty space) in the middle. Much better to just tell the disk to read one large stream between LBA A and LBA D, instead of telling it to read from A to B and separately from C to D, for small distances between B and C. In fact, this sort of trick should make ZFS somewhat bearable on SMR disks, in the right setting.
The fact that the disks cannot deal with a trivial optimization that improves their performance in what could have been a pathological scenario just screams "brain-dead" to me.
Between brain-dead firmware and deceptive practices, this does WD's image no good at all.
Well I’m never buying WD again after this.. my ironwolfs are performing great and I will be replacing my reds with wolfs when I’m out of space in a few months...
I haven't been following things very closely - I know that Seagate replaced some lower-end models with SMR units, but did they disclose that when they did?