The classic "it depends" answer applies here, along two axes: container assembly, and container execution.

If you mean "docker" the binary used to build container images, you don't even need that right now -- there are multiple projects that will build container images without involving docker or dockerd.

If you mean "dockerd" the container management engine that one controls via "docker" to start and stop containers, then yes microk8s will help as they appear to use containerd inside the snap (just like kind and likely all such "single binary kubernetes" setups do): https://github.com/ubuntu/microk8s/blob/master/docs/build.md...

Do you think Docker will disappear and everybody will some kind of "single binary kubernetes" on their machine + A tool to build the images.

Unlikely, although I for sure don't trust dockerd for my actual clusters anymore. I still use docker, and its dind friend, to build images because the whole world uses Dockerfile and the compatibility story between those alternative tools and the sea of Dockerfiles out there is ... tricky

I would love for something with more sanity to catch on, because Dockerfile as a format has terrible DX, but "wishes horses etc etc."