It's not a panacea, because hackers will be able to push arbitrary things, but you're greatly reducing your surface.
https://docs.aws.amazon.com/whitepapers/latest/aws-security-...
Further, we also use Veeam to backup Linux servers.. a high level read on how it works with immutable storage:
https://www.veeam.com/blog/v11-immutable-backup-storage.html
*Please point out how wrong this is.
The paypal switcheroo was dumb too
I guess the permission should be one way. The production server can only push data to backup server, never to delete or overwrite anything even if it wanted to.