This seems at odds with the multiple open source kubernetes distributions on the market. The problem isn't that Docker is open source infrastructure, the issue

This seems at odds with the multiple open source kubernetes distributions on the market. The problem isn't that Docker is open source infrastructure, the issue was that it remained too low-level as a container daemon, didn't manage to build a large community around swarm, and then were really late to embrace kubernetes. There easily could have been an alternate history where Docker Inc was the first one out of the gate with an enterprise kubernetes distribution, been a positive part of the community, and been a success.