I would say that the worst problem is the vendor changing the product in some incompatible way as part of a monetization strategy, so that Product X still exist

I would say that the worst problem is the vendor changing the product in some incompatible way as part of a monetization strategy, so that Product X still exists, but the install-base splits. Docker Inc. themselves make a big play of the facts that containers have to be standardized to be portable, and the portability is the key value. We could have done a lot of this stuff years ago if the virtualization vendors had a totally portable format for transferring VMs between different systems. Swarm etc. is part of the monetization strategy - other vendors in the ecosystem have already backed Kubernetes, or MesoSphere, or whatever, and do not want or need this stuff tied to the Docker run-time itself. Fortunately, Docker Inc. can add these without breaking compatibility of images or damaging the core features enough that a fork becomes necessary, but it does create market confusion.