While I don't think you are wrong... I have to wonder what % of the staff at Twitter that is. I'm sure their core application doesn't have a bus factor of 1 but

While I don't think you are wrong... I have to wonder what % of the staff at Twitter that is. I'm sure their core application doesn't have a bus factor of 1 but... a mass exodus of staff (5%? 10%? 20%?) could be an interesting problem.