What are you doing for DB backups? Do you have a replica/standby? Or is it just hourly or something like that? Because with a single-server setup like this, I'd imagine that hardware (e.g. SSD) failure brings down your app, and in the case of SSD failure, you then have hours or days downtime while you set everything up again.
Not every app needs 24/7 availability. The vast majority of websites out there will not suffer any serious consequences from a few hours of downtime (scheduled or otherwise) every now and then. If the cost savings outweigh the risk, it can be a perfectly reasonable business decision.
A more interesting question would be what kind of backup and recovery strategy they have, and which aspects of it (if any) they had to change when they moved to Hetzner.