This isn't binary as much as it's a continuum of abstractions already. Cloud servers already use virtualized disks where the actual drives can be in an entirely

This isn't binary as much as it's a continuum of abstractions already. Cloud servers already use virtualized disks where the actual drives can be in an entirely different building from the compute racks. Do you consider that separate? Separating storage and compute at the database nodes is just one architecture method that allows for simpler and more efficient scaling in modern cloud-based deployments where you have large pools object storage that's fast and close. I think you'd be surprised by what you can achieve with some metadata and caching.