That being said Nomad's CSI support doesn't impact clusters that don't optin to use it. Jobs that use host volumes or ephemeral volumes still work. Only using Nomad for stateless workloads still works. We try very hard to introduce new features in a way that only impacts people who use them.

While the principle is the same for CNI, our migration to group networks ("groups" in Nomad are like "pods" in k8s) and away from task networks has been more painful than we had hoped. Existing jobs should still work with task networks and we're rapidly trying to fix differences in the two approaches.

Nomad's Consul dependency does introduce complexity. The migration to group networks actually included a change that made service addressing available to servers in such a way that Nomad could offer native service discovery. It's still being discussed whether we want to pursue that since offering multiple solutions has obvious downsides as well.