I've had similar experiences with them.

Had a CPU cooler fail somehow (resulting in one very toasty, unstable server) and they responded within minutes, the whole thing was probably resolved within half an hour.

I've had exactly the opposite experience with Hetzner support. Slow to respond. Difficult to convince that hardware failure has occurred and never less than 3 hours, often more than 5 to get it replaced.

I'm guessing the difference comes down to failures they detect first, vs. failures you detect first. If they have a monitoring system that tells them something broke, they'll immediately go and fix it. If you tell them something broke, they'll have to go check. If you tell them something broke and they have a monitoring system that says it's fine, then you'll likely have problems.

If you are talking about dedicated servers: Those are unmanaged, Hetzner does not monitor those.

Regarding grandparent: What kind of hardware failure? I had to change different types of hardware in the past. For HDD changes you send a full SMART result + possibly the logs showing that the RAID kicked the faulty disk and they replace the faulty disk in 30 minutes (and one time even apologized that it took 2 hours for a low-priority-support server). In all cases the actual downtime was < 5 minutes, because of RAID. For possibly broken fans I simply stated that according to my Munin logs show consistent temperatures near the upper limit and asked whether they could take a look. They added an additional fan within 30 minutes, again with actual downtime < 5 minutes.

Most of my replacements were during the night in Germany, that might have helped, because there are possibly less requests in parallel. And I always had hard logs proving my HDD failures.

I'm very satisfied, too. Servers are ready in minutes, not hours, after ordering. We currently run ~30 servers there (dedi) and over the last ~7 years roughly had 1 HDD fail per year. Each time the replacement was done on our chosen time and quickly in about 5 - 20 minutes (the installabled images come with pre-configured software RAID 1). We recently tried a AX60 (Ryzen 7 1700X Octa-Core) and had some sporadic crashes, support changed some BIOS settings, no problems since. Service and prices are unbeatable, imho.

I know this is silly, but I would have laughed like crazy if your comment about using their reliable services ended with your comment stopping halfway (like your station/internet died).