When I setup my backup strategy, the Hetzner storage boxes showed the best price per TB, and allow ssh / SCP and webdav access.
I run a virtualized TrueNAS Scale with a passed through HBA and about 6 drives in raid-z2 mode. I setup TrueNAS to do regular snapshots - hourly, daily, monthly and I use the built in encrypted backup options to backup my most important data every night (personal videos and pictures, VM backups, documents, docker volumes).
This works like a charm and it seems to be also quite stable. If the system ever dies, I can always simply mount the encrypted backup folder on my laptop using rclone, and then manage my files directly using mc.