Considering Google, Azure, AWS, DO, IBM and others all have cloud offerings centered around Kubernetes with Docker compatible containers, even if some of the tooling changes, I don't expect that "Docker" will really go anywhere. I would be surprised if the next step doesn't have it swallowed by one of the above companies (probably not DO though).

Even for AWS Lambda, I use docker to build linux lambda packages on non-linux environments (docker for windows/mac). The easiest way to get a service up in Elastic Beanstalk is with a Dockerfile.

Even if Docker (organization) does die, Docker (open source tooling) will live on for a very long time. And although I do like where podman and others are coming from, I don't think that it will displace docker in the long run.