Encrypting your backups stops thieves. It does nothing against ransomware. You confused the two.

Encrypting your backups stops thieves. It does nothing against ransomware. You confused the two.

Ransomware doesn't read your backups, it deletes or encrypts them. Your AES-256 means nothing when the attacker just overwrites the bucket.

What stops them is immutability: object-lock, WORM, append-only repos with a key the server can't revoke.

— Encryption: confidentiality, useless vs deletion
— Immutability: the only thing that survives ransomware

Encrypt AND lock. But if you only did one, you picked the wrong one. Fight me.