I think the difference lies between harm and disagreement. How can it work? I don't know or have all the answers, as I've never even seen community accountability in action at a small local scale.
This highlights to me the importance of learning how to do this stuff.
I don't think it's as complex as you're making it. Community accountability works through shared cultural standards and social pressure to conform to the status quo; Google employees don't have shared cultural standards, and the whole problem here is that some of them don't think it's right to conform to the status quo. The reason you've never seen it in action is that, in a multicultural society, it doesn't work on any scale larger than a friend group.
This highlights to me the importance of learning how to do this stuff.