Docker cloud offered CI/CD integrations and management features similar to K8S that were proprietary to them. While Docker images themselves are portable, this is a whole different beast.
in other words, for the micro-service world, you don't have the monolith, the whole stack is the monolith?
It seems like they are only discontinuing the hosted swarm part for now and keeping the rest up. That said, it may just be a matter of time before the great of the stuff goes down.