To disambiguate it’s necessary to separate Docker the runtime from OCI image format, commonly still referred to by a lot of people colloquially as “Docker Images”. Docker the desktop software, file format and CLI is still very much used professionally to build and test OCI images, which then run in Kubernetes. Docker as a container runtime platform (and orchestration with Swarm) is what is generally going out of vogue.

Although a pattern I commonly see these days with a lot of OSS projects is that oftentimes they provide a docker-compose.yaml even though no one at any reasonable scale is running Docker Compose in production. This is simply because Kubernetes setups are complicated, weighty, and heterogenous, and often not running on your local machine and Docker Compose is a great way to do a hello world style demo of your container-orchestrated app (because everyone still uses Docker Desktop).