On Wed, Jul 21, 2021 at 6:47 PM David Sterba [off-list ref] wrote:

For the record summing up the discussion from IRC with Zygo, this
particular firmware 80.00A80 on WD Green is known to have problematic
firmware and would explain the observed errors.

Recommendation is not to use WD Green or periodically disable the write
cache by 'hdparm -W0'.

Thank you for the reply, yes, from now on I intend to disable write
cache on those disks, since I still have a lot of them in use.

Jorge