This sounds like a nifty solution for compute, but I suppose for data storage and such you would want a separate managed service? Or does this hook into that for various providers too?
You can specify the default storage class to use the provider's CSI driver. The PVC is then specified and consumed the same way in a portable manner across providers.
You can also choose something specific like a mounted hostVolume which is not provider specifc.
Cutting edge stuff like NVMe-oF is even possible, the CSI ecosystem is very active. https://github.com/spdk/spdk-csi
For single server, I'd just use sqlite.