First, if I understand it right... Google does some smart things in upgrades. They do things like tests and then upgrade their equivalent to AZs in a data cente

First, if I understand it right... Google does some smart things in upgrades. They do things like tests and then upgrade their equivalent to AZs in a data center. I'm sure there have been upgrades gone bad that they've had to fix. Kubernetes can be upgraded. I've watched nicely done upgrades happening 4 or 5 years ago. I've watched simple upgrades happen more recently. It's not unheard of. Even in public clouds I've upgrade Kubernetes through many minor versions without issue. I would argue it's more work to create more clusters. You need to migrate workloads and anything pointing to them. It also would cost more as you have to run more hardware.