Because Kubernetes is both abstraction and de facto standardized platform across infrastructure providers. All deployments to customers who are large institutions start with provisioning, OS alignment (there are huge differences between RHEL, SLES, Debian or Amazon, then customisations like hardenings are put on top), networking, storage, access rights. You don't want to deal with that from scratch each time. It costs both time and money. Direct dealing with hardware is long gone (Hyper-V and VMware), and now it's time to cut out the upper layers. Also, Kubernetes allows better resource utilisation and scaling.
