You could be right. But how do you know the consultants Musk hired are wrong? How does Eric know? Maybe there was a situation found where that did, in fact, happen. Certainly with a large number of microservices, it could happen. Maybe Musk is saying "edge case" and Eric is saying "on average." Personally I feel outside consultants could have very well found problems that the internal team did not see.

What everyone agrees on is that Twitter's architecture is deeply broken. Eric's been there six years, so he's probably at least a little culpable in that. If I'm Eric, and was part of a team that fucked up that badly for six years, I certainly wouldn't argue back with that much confidence.