5
You could try something S3 based, and do backups by date?
For example, export a subset of the DB and name it accordingly (ie. 2025-04-to-2025-01.tar).
If you do that there are a lot of pretty cheap S3 providers (like Wasabi).
S3 interfaces nicely with RCLONE so you can move providers etc and pull it really quickly.
As an aside, when I looked into something like this the thing that made me hesitate was the time and cost for retrieval from cold storage (like amazon glacier) outweighed the savings.