> I wouldn't be surprised to see established companies expand on cheap real estate and start offering closed offices to employees.

As much as I like closed offices, I think that companies that want to save money still won't offer them. The cost of closed offices isn't just more square footage; they also incur construction costs that open office space don't: walls, doors, their own heating/cooling/ventilation ducts, their own lighting and electrical wiring, etc. And an office layout with closed offices is more expensive to modify.

Warehouses is another one (in addition to coworking). I am not sure how easy it would be to rezone (some places have an industrial category that is separate from office/residential) but being able to fulfill orders out of city-centres is obviously attractive (but debt and equity would go to zero then, you could probably maintain prices with coworking but warehouse space is going to be a 90%+ loss).