Commercial real estate value is directly connected to occupancy. If I own an office building which was valued ten years ago at $10M (to pick a random number) and today is valued at half that because nobody's going in, that's a direct $5M loss on my accounts, and any loans outstanding secured on it are potentially now underwater. Not only that, but it also weakens the rent I can demand from the tenant not just because the value of the building has dropped, but because they demonstrably don't need all that space any more.

Microsoft is almost certainly a special case in a number of ways, but the incentives are absolutely there for commercial landlords to try to force their tenants' hands.