Pricing is falling rapidly for storage. Consider that S3 - IA is $15/mo for a TB, and backblaze B2 can offer 1 TB for $5/mo. I would assume both are making some profit at those price points, so $12/TB/mo should be workable if the service is doing their own hardware.

Backup services especially have low operational requirements for their hardware and network connection, since once the files are uploaded they only need to be verified periodically.