To organize and back up 23 TiB of personal files:

1. Use BorgBackup for local backups due to its encryption and deduplication features.
2. Pair Borg with rclone for transferring backups to cloud storage.
3. Consider inexpensive VPS providers like InterServer or rsync.net for online storage.
4. Implement a 3-2-1 backup strategy: 3 copies of data, 2 local on different devices, and 1 offsite.
5. For aggregation, use IDE to USB docks and deduplication tools like fdupes.

This setup ensures security, redundancy, and easy recovery.