I know open office plans aren't popular on hacker news so this is preaching to the choir, but I think that meetings and open office plans are symptoms of the same issue: managers don't have enough direct control over success. They get to set everything up (hiring, organizing teams, prioritizing) but then, like a year-long rube Goldberg machine they have to watch and wait to be needed. I know if I was in that position I'd go crazy and start trying to directly manipulate success, which may take the form of meetings, "hackathons", and forced collaboration.