Reliable is a flexible word. Hetzner does frequent, albeit often brief, maintenance operations that would incur a down time on a high-throughput live service. Not impossible to design around with enough redundancies, but far from "I have one FreeBSD box that's been up for 467 days with 100% uptime" that people used to brag about in the early 2000s. I have few VPSs and bare metal instances that I just `sudo reboot` when there is a kernel update with practically "zero" impact or downtime for myself. Something unimaginable to do in a production system where you need to cordon, traffic drain, update, reboot, uncordon then orchestrate that across an entire fleet of instances with different roles and characteristics in a specific order.

>Hetzner provides cheap and reliable vms.

True, i have some hetzner (not vm's but metal), and Vultr (just vm's), i just had one bad IP until now (i just changed it instead of trying to get it removed from a blacklist)