> I haven't heard of Debian, Ubuntu, or RHEL update that would bork the system in a long while. All of these distros are more than capable of running containers.

Fedora CoreOS is designed to have the smallest possible attack surface out of all operating systems currently capable of hosting containers.

Unlike Ubuntu, Debian, and CentOS, Fedora CoreOS doesn't contain packages that aren't required for hosting containers, and is automatically kept up-do-date without any manual interventions.

Just like Chromium OS on PCs, Fedora CoreOS on servers eliminates the need for "dist-upgrade", and thus reduces risks and increases reliability.

> And, for corporate use? You'd use Debian + Kubernetes to take care of your needs, wouldn't you?

CoreOS is designed for these workloads. For example, with OpenShift 4 (Red Hat enterprise Kubernetes) the masters run on RHCoreOS and the worker nodes have the option of running on RHEL or RHCOS. You can end up having your entire Kube platform running entirely on CoreOS, either bare-metal or virtualized.

Fedora CoreOS is big as OCP uses RHCOS. OKD (the community version) needed its own platform and FCOS is that platform.

CoreOS is designed to remove everything you don't strictly need to run containers and to allow for automatic-upgrades across multiple machines (ie: don't reboot everything at once). That means you have a minimal amount of things that can be hacked and easy automatic updates for the rest.