I believe they are referring to the dumpster support model. The hardware is so cheap that, if it fails, you toss it in a dumpster and buy more by the gross. Using Kubernetes to spread loads across your less reliable nodes ensures high availability. Sometimes this can be even more reliable because you are regularly testing your recovery and backup features and your hardware is more varied.

The downside is that if some piece of firmware or hardware has a vulnerability you have a larger attack surface.