Not exactly. Kubernetes has a much larger development community than Swarm, and therefore its overall development throughput is of course higher. At the same time, Swarm is narrowly focused on a single use case: integration with the Docker platform. This narrowed scope allows for more rapid development cycles. When a Docker customer asks for a feature, it can be implemented in Swarm, integrated into Docker, packaged and released, more rapidly than the corresponding feature in Kubernetes - not because Swarm developers are smarter, but because they have a narrower problem space to worry about.
This focus and rapid development loop makes Swarm extremely useful to Docker and its users, even as it embraces Kubernetes and integrates it into the platform. It also benefits the Kubernetes community: they get an incubator for new ideas and designs which they can then generalize and adapt for their own uses. Again - this is a natural result of focus, not a sign that one project has better ideas than the other.
Examples of this "incubator pattern" include: Windows support; secrets implementation; user experience for node promotion/lifecycle.
Encryption at rest was introduced in Kubernetes 1.7, making it usable in production. This was done in collaboration with the Docker security team, which had previously implemented encryption at rest in Swarm.
Further reading:
https://github.com/kubernetes/kops/issues/3356
https://kubernetes.io/docs/tasks/administer-cluster/encrypt-...
...but they weren't all that 'secret' [1]
1.https://medium.com/on-docker/secrets-and-lie-abilities-the-s...
