I think that the majority of unhappy open-office employees are more upset with distractions than with the lack of privacy.

The widespread application of headphones to "solve" this problem is silly. It does nothing to screen out the visual distraction of working with 40 other people in your sightline, and it cuts you off from meaningful discussions with your direct peers.

I've been happiest in spaces where workgroups of 6-8 people were in large-ish shared offices that broke up sightlines and isolated noise. Doors that close, folks (partially frosted glass or not).