The key word is might. I remember a similar HN discussion a few months back someone mentioned that because they happened to overhear a conversation between two engineers they were able to save weeks of them working on the wrong thing.
Anecdotes like that aren't signs that open offices are successful or result in "having good communication" - it means you have horrible communication and you got lucky. What if that conversation happened while the person who serendipitously overheard it was in the bathroom? Or on vacation? Or in a meeting? Or wearing headphones? Good communication means not relying on chance to prevent engineers from wasting their time.
Like I said, it is possible to get communication right without having an open office plan. But at least with an open office plan, you have the bare minimum set up. And for big companies, the bare minimum is already better than average.
The same for small companies. If you are with 5 to 10 people, not everything will be officially communicated through email. You know stuff because it happened in the same room as everyone is sitting in.
If everyone is inside his or her own office, your company depends on having good email or message communication. Everyone should include the right persons when sending emails, planning meetings, etc ... . This is not impossible of course.
When you have an open office plan, your communication becomes 'in your face'. You might overhear things that are also relevant for you. You see or hear a lot more than through official communication channels alone. And that is probably the reason to their success. Of course interruptions etc are disadvantages, but nothing beats having good communication.