Meetings are not inherently bad. For example, if I want to talk through some technical architecture diagram with you I will ask when you're free and schedule a meeting. That is a potentially useful meeting and a good way to share information.
Bad meetings are normally have some of the following characteristics:
* Too many attendees
* Only a subset of attendees do the talking
* No agenda
* Reoccurring
* Serve the purpose for one person rather than the group
* Are for planning about planning
* Are too high level - not getting into details
According to Sahil, he runs almost everything async.
It didn't last, though. The people who felt they were the smartest in the room left to other companies, and this continued until it was left with people who wanted to be the smartest in the room.