I tend to just store all my backups off-site in multiple geographically distant locations, seems to work well

Genau

Matrix is a solid option, a lot of activity there as well

I use restic with a Hetzner StorageBox for most things and also BorgBackup to the same StorageBox for other things both are great options

Both options support SFTP so theoretically you can backup to wherever you want, I personally use Hetzner due to it being cheap and off-site

Where did you get this??