Snapshots are not backups they are a point in time picture of any given VM.
To do a restore of a VM you need all the files associated with a VM not just a snapshot.
Snapshots are meant to be used as a quick restore point when upgrading/changing apps ect...so can you revert to that if things go south. However if the VM itself goes belly up your snapshot goes with it.
In short do a real backup using VCB or Veeam or other apps designed to do a real backup of the VM.