Hi LucD, I've read may of your post as I'm trying to come up to speed with vsphere and powercli.
The reference to vmhostinfo is just a bad cut/paste putting together this post.
I've got 2800 VMs and each one is showing a runtime.powerstate = "PoweredOff". Which is really odd since the loop of virtualmachines includes the filter
-Filter @{"Runtime.PowerState"="PoweredOn"}. The filter works fine. (I don't want the filter, just using it for troubleshooting)