> I mean, it's plausible, yet I find it hard to believe this solely drives demand 5 times. Because if it does then what, companies were not using cold storage backups before?

As someone in HPC: people never delete stuff. It can stick around forever, and so if more bits are generated, there are more bits that people don't want to delete "just in case". Depending on the organization, quota enforcement can be tighter or looser.

HSM is fairly popular in the HPC space for this reason:

* https://en.wikipedia.org/wiki/Hierarchical_storage_managemen...

Your newest/hottest bits are on NVMe, anything older than (e.g.) 3 months gets move to SSD, anything older than that to spinning rust HDDs, and then to tape.

There are several file systems where this happens in the background: the file still shows up at /path/for/stuff/foo.txt but the contents are shuffled about behind the scenes.