datahoarder

if you backup locally so not over a network share you could use Backblazes Personal Backup ( https://hub.docker.com/r/tessypowder/backblaze-personal-wine ) it's like 8$ for unlimited backup

but they have some kind of tracking for blocking cifs/smb shares but you can circumvent that using dolany my current setup as my data is mainly just a Hetzner 20tb storage box I have a second windows VPS that mounts that CIFS storage using dokany und Just run backblaze Personal backup there was a real hassle to set up an the backup takes for ever but yeah it works

What you also might consider is re-encoding your stuff to use less space. Photos can be stored as lower quality jpgs and home movies can be reencoded as hevc. The latter can even be done automatically using something like tdarr.

I use AWS S3 Glacier Deep Archive. 30 TB would cost you about $27 per month.