Anecdotal? There's a great New Yorker article[1] that references a number of studies. This blog post[2] links to a couple others and addresses costs/alternatives. A "study of over 40,000 survey responses collected over a decade has found that the benefits for workers are quickly outweighed by the disadvantages"[3]. Here's a Washington Post piece[4] on office furniture designers realizing (citing multiple studies) "open-plan spaces are actually lousy for workers." A TIME article[5] highlighted decades of research that associated open layouts with "greater employee stress, poorer co-worker relations and reduced satisfaction with the physical environment."

[1] http://www.newyorker.com/currency-tag/the-open-office-trap

[2] http://nathanmarz.com/blog/the-inexplicable-rise-of-open-flo...

[3] http://theconversation.com/open-plan-offices-attract-highest...

[4] http://www.washingtonpost.com/blogs/on-leadership/wp/2015/04...

[5] http://ideas.time.com/2012/08/15/why-the-open-office-is-a-ho...