Reserved Block Count Chip.
I am unsure whether this is reserved space for a RAID controller, or a hidden partition. It may be that the storage for this reserved space is failing, or it may be a false positive from
smartctl if there is no reserved space. I looked at the documentation for
smartctl but could not find what it was referring to with regards to this parameter. Here is a nice list of SMART attributes, although I couldn't find a 1:1 mapping with
smartctl names against what is in that article.
Note that this may be a result of the "reserved block count chip" failing. If the chip returns 2TB of reserved space and the disk is only 256GB then this test will fail (or something like that).
Also, also aren't SSDs much more immune to these types of failures?
Citation Needed. SSDs will be equally prone to controller failures, as for storage life I don't trust an SSD to last longer than my magnetic drives (I have had reliable magnetic drives for 10 years+).
Also while you're thinking about SSDs vs magnetic, consider the data recovery options. I know if my copy of Windows stops booting off a magnetic disk I can take that disk to another PC and do some data recovery (minus whatever's lost in bad sectors). You lose a flash chip on your SSD... you just lost a big chunk of your data.