I assume in your analogy the general population is still buying the same amount of grain, so losing a silo of grain to rot is a pure loss to the farmer, and in a way is a loss to grain buyers (prices have to go up slightly).

But in the office space scenario, less office space is being used overall. This means that yes, landlords are losing the value of their investment, but (former) tenants are gaining access to cash flow that would have been tied up in rent and maintenance. So value has not been destroyed in the same way it was in the silo example.

I don't know if this is a good or bad thing, just pointing out a material difference in the two things you're trying to analogize.