I think there are a couple of lines of thought related to this. I’m one person with a NAS so I don’t need multiple volumes. I can certainly get by with a single volume on each storage pool and this will simplify management of things.
If you were working with enterprise grade storage in a corporate environment, having multiple volumes will make sense. I think of this as carving up disk space for production SQL Servers where each drive letter corresponds to a given volume which resides on a given storage pool. A volume can serve multiple folders.
You know a blog post is going to be good when it starts with “In hindsight, I should have done this differently.”