When I was at IBM, post acquisition, they were trying to move a company into open space from their existing offices and the former CEO presented them with incontrovertible evidence of work productivity vs offices vs cubes vs openspace vs individuals. To explain that to maximize work done per unit time they needed a mix of offices and open space, just open space would harm the productivity of the team. The VP on the line kept falling back to "but everyone else has to do this" and "you aren't seeing the big picture" kinds of arguments. It was really sad.
The truth is that "office space", which is to say the number of square feet (or meters) of office space you need per employee is a "cost." And that cost is computable, whereas the cost of less productivity, or inability to attract the best talent, are not. And when you run your company with accountants they go for the "known savings" over the "potential gains" every, single, time. You can put more employees in a building that is "open plan" than you can in one with cubicles, and much more than in a building with offices. So the accounts force this on the company and senior leadership doesn't have the stones to contradict them.