Backup using SSH (or borg backup)

Currently one can create remote backup storage using SMB/CIFS or NFS. Both protocols are not really suitable for offsite backups over the internet.

On the other hand, SSH (SFTP) is quite suitable for that process.

ISPs (like Hetzner) provide a cheap “storage box” product, which would work quite well in such a case. It also supports the borg backup protocol, which would be even better, supporting client side encryption of the backup data.

There are many add-ons built to do exactly what you ask.
Search out some of those.

You are asking for what has been defined as a non-core function be added as a core function, and those changes are few to come by.

These cases are specifically why add-ons exist.