And yes, there is less fancy companies like one where I work where we don't use Kubernetes because it's kind of overkill if all of your production workload fits onto 2 beefy bare metal servers.
I can see a point in using Docker to unify development and production environments into one immutable image. But I have yet to see a normal-sized company that gets a benefit from spreading out to hundreds of micro instances on a cloud and then coordinating that mess with Kubernetes. Of course, it'll be great if you're a unicorn, but most people using it are planning for way more scaling than what they'll realistically need and are, thus, overselling themselves on cloud costs.