Great product, sort of a shame about the price
This actually makes a lot of sense for offline storage, but only in certain situations. I have been working with someone looking at getting into 4K RAW video production which means you're looking at data rates of 250MB/s. When you're talking about filling a £250 6TB hard drive with four hours of processed video, being able to move them to LTO6 tapes costing £30 each makes sense, even given the cost of the drive.
For those of us that aren't producing 4K RAW videos on the other hand, I see little benefit of using this for "personal" storage over a bunch of external SSDs.