Encrypted storage of what? Files? That would probably be via Blossom rather than Nostr.
Thing is, if I want to have private and encrypted file storage that I can access from anywhere, that's what my home server is for. Don't really need a "cloud" option except perhaps as a redundancy, since I run my own "cloud."
I use Blossom to store files I want to share with others on Nostr, so encryption isn't necessary for that use-case most of the time. The exception would be for sharing a file via DM that I ONLY want the receiver to have access to.