The original article seems to group all open office plans into a single category, as if they were all alike.
I've worked in two notable different open office plans. One was at around 400 square feet per person. In this one, the only people with an office were those that dealt with sensitive documents that had to be in a filing cabinet (in this case that was one person, the accountant, who did payroll).
I've also worked in an open office where the "senior" staff had offices with windows looking into the cubicle area. The open area was around 150 square feet per person. While sitting at my desk, the back of my chair was about 4 feet from the person behind me.
These two experiences were drastically different in productivity and focus. To say open offices don't work, because most of them don't work is like saying startups don't work because most of them fail.
The problem isn't with the idea, it's with the execution.