Paul Graham expressed this much more strongly than I have, and he wrote about it over 10 years ago:
"After software, the most important tool to a hacker is probably his office. Big companies think the function of office space is to express rank. But hackers use their offices for more than that: they use their office as a place to think in. And if you're a technology company, their thoughts are your product. So making hackers work in a noisy, distracting environment is like having a paint factory where the air is full of soot.
The cartoon strip Dilbert has a lot to say about cubicles, and with good reason. All the hackers I know despise them. The mere prospect of being interrupted is enough to prevent hackers from working on hard problems. If you want to get real work done in an office with cubicles, you have two options: work at home, or come in early or late or on a weekend, when no one else is there. Don't companies realize this is a sign that something is broken? An office environment is supposed to be something that helps you work, not something you work despite.
Companies like Cisco are proud that everyone there has a cubicle, even the CEO. But they're not so advanced as they think; obviously they still view office space as a badge of rank. Note too that Cisco is famous for doing very little product development in house. They get new technology by buying the startups that created it-- where presumably the hackers did have somewhere quiet to work.
One big company that understands what hackers need is Microsoft. I once saw a recruiting ad for Microsoft with a big picture of a door. Work for us, the premise was, and we'll give you a place to work where you can actually get work done. And you know, Microsoft is remarkable among big companies in that they are able to develop software in house. Not well, perhaps, but well enough."
from Great Hackers section called "The Final Frontier"
http://paulgraham.com/gh.html
I agree that open plan is the worst, but cubes are a close second, and both types of space are not as cost effective as private offices (even in dense urban areas).
If the executives want to be "egalitarian" about it, then raise the conditions of everyone up. Don't act like a proud martyr and lower your own conditions. It's patronizing and solves none of the problems. Plus, executives who do this will always find other status games to play if they want to feel superior, so it's never really egalitarian anyway.