I would rather play realistically with 32 players than have my opponents survive an artillery-strike by sitting in a wooden shed or not being able to move my tank over a barbed-wire fence.
I heartly agree about those fences
It mostly depends upon in how many "chunks" you seperate the Destroyable objects, lets take your Wooden Shed.
One could model it in a way that every wooden plank can be destroyed on its own, with only two states (intact/destroyed) or something in between. Since every Client connected needs to know the status of each destroyable part of the Shed, this can be an enourmous resource hog.
As the Vids show, Fences are destroyable by Artillery.
So i guess we won't be stopped by fences, just that we didn't see a vid yet showing us a Tank driving over fences doesn't mean it ain't in.