Once you have VSAN configured and enabled, you may find that you are unable to create storage policies because VSAN storage providers are not registered. This process should happen automatically but, if the providers become unregistered, then we will need to force the system to refresh the provider registrations before VSAN policies can be created, modified, or applied.
It is likely that there is a provider registration problem if the VSAN-related policy options are not present when you go to create a storage policy or if no policy information is reported for VMs/virtual disks.