You should spend a week working on a infra / ops team then.

I worked with multiple ops/infra teams, and have seen standard server rooms and advanced server rooms. They’re not supposed to have pipes leaking on the racks, that’s ridiculous. I know many stable redhat servers that didn’t need to reboot for years. I also maintain websites on hetzner servers that haven’t needed to reboot in years, under pretty high load. On the other hand, I got a hostnoc dedicated server and that thing went offline three times a month. So yeah, you have to know what you’re doing regardless of whether you’re building a server room or a k8s cluster.

More modern data centers have liquid pumps available for low-cost cooling.

So, we do ~daily restarts on our customers' systems. We have a solid 12 hours per day to patch up a server before it needs to be in production again.

That said. We communicate directly with other systems on the same premises that probably haven't been rebooted in over a decade.

Building something that can run 10 years without downtime is not happenstance. It is very intentional and deliberate engineering.

As mentioned above, they were, both RedHat and Ubuntu now support kernel updates without restart.