
VMware vSAN should manage better VM snapshots compared with traditional storage and VMFS datastores. The reason is the new (v2) on-disk format in VSAN 6.0 and the new filesystem that is used: VirstoFS.
VirstoFS is the first implementation of technology that was acquired when VMware bought a company called Virsto a number of years ago.
Also there is a new sparse format called vsanSparse. These replace the traditional vmfsSparse format (redo logs).