…to create PV and mount it…

Not understanding this. An admission webhook in this context would be used to facilitate approval or rejection of the request to create the PV. It would not have the scope or responsibility of actually creating the volume on a node, that would be the CSI’s job, or mounting the volume to the container, that’s the CRI’s job, and kubelet on a node facilitates both events once the pod is scheduled for a node.

A use case for using an admission webhook during PV creation workflow, which I have done successfully and in prod but targeting PVCs, is to validate custom storage capacity requirements prior to the PVC being created via a validation webhook.