I’ve used hetzner cloud for around 18 months and no data loss so far.
Generally as per their FAQ they do have redundancy in their data storage as described in FAQ.
Servers with local disks keep all data on a local RAID mirror on the host system. They are optimized for high I/O performance and low latency and are especially suited for applications which require fast access to disks with low latency, such as databases.
Servers with ceph disks store their data on a remote filesystem. Each block is stored on three different servers. They are especially suited for higher availability needs: If the local host hardware fails, we will boot the server on a different machine.
data on their volumes is triple duplicated
We store every block of data on three different physical servers (triple replication).
and you also have option to create additional backups and snapshots: