I've described this as "Nomad is a container orchestrator, while Kubernetes has a container orchestrator".
Nomad, Consul and Vault interoperate extremely well and are mostly pleasant to use, but I found myself missing the rest of the ecosystem pretty quickly, especially around ingresses, and I think they made the wrong decision on the networking model compared to Kubernetes.
That said, I haven't played with Consul Connect, the Consul+Envoy service mesh, yet. That might address a lot of the problems. But fundamentally I can't help but think that Nomad and Kubernetes both made a run of it and Kubernetes came out the winner of mindshare and ecosystem.