Nomad isn't a cheap imitation of Kubernetes but all these components taped together are. Kubernetes is no less composable than a system built on Nomad, it just includes more functionality from day one.
If you're running containers with a orchestrator like Nomad, at some point, you'll need DNS. So you do it yourself and then you're managing Nomad and DNS. Then (we'll assume, because you're using a container orchestrator to manage multiple services) you'll need service discovery, so you write some jobs and event handlers to glue together Nomad and your DNS solution. And then, because you're a team of responsible people, you'll want to store secrets securely, so you graft in Vault. And then, you realize zero-downtime config changes would be great, so you slap Consul in there and write some sidecars or library code to handle config updates. Then metrics. Then logs. Then rolling deployments. And it continues, indefinitely, as you add features.
If you started doing this five years ago, fine. If you start doing this today, you're out of your mind. You're just doing work for the sake of "but it's composable". There's a reason why teams still build applications on frameworks like Rails and Django even though they don't need half the features--it's more important to them to get something functional up and running than it is to satisfy delicate sensibilities about only using what's needed. Kubernetes is the analogue in the world of systems and operations.