VMS developer Network Optix has released detailed camera usage stats - 2017 IP Camera Report. While some VMSes collect such data, I have never seen one make it public.
Network Optix became collecting anonymous usage statistics last year on camera brands used, resolution, etc., such as:
Note: the above stats exclude Digital Watchdog devices and other Network Optix OEMs, otherwise DW would have a much higher showing on this.
Other thing to keep in mind is that Network Optix is a relatively low cost VMS (sub $100 licensing typically) so it would tend to be paired more with lower cost cameras than say Genetec or Milestone.
Related, see our test: Network Optix/Digital Watchdog VMS Tested